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T a b l e o f C o n t e n t s

CAGE NO. 56878

Page

SPS Technologies Certified Socket Head Cap Screws 3-4

Engineering Service 4-5

Special Warning 5-6

Socket Head Cap Screws, 1960 Series 7-14

Socket Head Cap Screws, Low Head Type 14-17

Button Head Screws 18-19

82° Flat Head Screws 20-21

Button Head and 82° Flat Head Screws 22-23

Shoulder Bolts 24-26

Set Screws 27-28

Do Your Socket Screws Measure Up? 29

Understanding FF-S-86 30

Fasteners That Don’t Meet MS & NAS Specifications 31-34

Limited Warranty and Exclusive Remedy 35

3

SPS Technologies CertifiedSocket Head Cap Screws

The complexity of producing fasteners to theFF-S-86 specification demands absolutecontrol of each process throughout themanufacturing system. The consequences ofa breakdown in any area could be partfailures and serious losses.

Proper quality assurance standards shouldsubstantially reduce the number of flawedparts. But a higher assurance of qualityresults from statistical process control of acomplete “in-house” manufacturing system—from design to the finished part. Thisprovides certifiable control of the quality ofeach lot of fasteners at every phase ofmanufacture. SPS Technologies AerospaceFasteners Group maintains this type ofcomprehensive “in-house” system.

THE Advantages of SPS SocketHead Cap Screws• Tensile strength levels maintained at190,000 and 180,000 psi—higher thancurrent government and industry standards• Superior fatigue resistance resulting fromadvanced design, mechanical properties andclose control of the manufacturing process• Deep, accurate socket for high torquewrenching• Precision forged for symmetrical grain flow, maximum strength• Fully formed radiused thread increasesfatigue life• Controlled heat treatment producesmaximum strength without brittleness

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Product Testing and Certification SPS never takes short-cuts in the manufactureof socket head cap screws to assure that youreceive consistently high quality products thatmeet the FF-S-86 specification.

Product quality control includes:• Process control from lot to lot to decreasevariation and increase consistency• A larger percentage of fasteners — in manyinstances — undergo increased inspectioncontrol measures• In-process metallurgical inspections includetests for tensile, hardness, stress corrosionand stress durability on plated parts• Comprehensive dimensional, discontinuity,mechanical property (hardness and axialtension or wedge tension testing),metallographic (carburization anddecarburization examination) testing• Inspection lots per FF-S-86—screws aresame type; same size; same length andthreads; made from the same heat of material;have the same heat treatment, protectivecoating and surface treatment • Final inspection is performed on dimensionsto achieve zero defects. This criteria is muchmore rigid than that required under the ASME specification

PlatingSPS Technologies’ Jenkintown facilitymaintains a unique, on-site high technologyplating facility to ensure complete control of this critical process for socket head cap screws. Designed and developed by SPSTechnologies, this plating facility usescomputer-controlled equipment to assureuniform quality from part-to-part and lot-to-lot.

Computer control also provides the ability tomaintain exact plating thicknesses andtolerances to preserve precision thread fit andmeet specifications. What’s more,repeatability is enhanced with the capability to store part history and formulas forsubsequent orders.Plating Highlights...• The SPS Technologies plating facility canproduce four different platings at once andcan perform rack & barrel plating• SPS uses a 23 hour bake within four hoursof plating to minimize the embrittlementpotential• Stress durability testing capability to confirmhydrogen embrittlement relief treatment

Engineering ServiceSPS Technologies has the experience andresources to meet your most exactingrequirements for the application of certifiedsocket head cap screws in criticalapplications...

• Nearly a century of experiencemanufacturing high quality, precisionfasteners and components • Unique capabilities to provide totalresponsibility for all phases of productioninvolved in the precision manufacture offasteners• Expertise with special materials, closetolerances and critical dimensions• Comprehensive testing and designengineering services• Stringent quality assurance for all products,including Statistical Process Control (SPC)

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Special Socket Head Cap ScrewsWhether your application requires a slightmodification of a socket head cap screw ora completely different configuration, SPSTechnologies can meet your requirements.Special materials, sizes and finishes can allbe supplied to your specifications.Our engineers, supported by experiencedtechnical staff, are ready to help you solveyour fastening problems. Fax a descriptionof your application and special needs forprompt no-obligation assistance.

Telephone: 215-572-3000Fax: 215-572-3133

Special WarningFailure to provide qualified sourcecontrolled parts where specified can resultin harsh penalties.

The source controlled parts in question areNAS 1351 and 1352 socket head capscrews. Regardless of who purchases theseparts initially, if the end-user is BOEING,then the manufacturer must be listed in theBoeing D590 standards. To assume theseparts may not be going into a Boeingprogram is inadequate and irresponsible.

Harsh PenaltiesThe temptation to supply parts based solelyon price from sources not approved byBoeing is great. However, Boeing has statedthat failure to comply with Boeingspecifications and the D590 standards pagewill result in the scrapping of parts at the

seller’s expense, cancellation of thepurchase order and removal of thesubcontractor from the authorized bidderslist for a minimum of (30) thirty days. Repeatviolations will result in harsher penalties.

SPS IS AN APPROVED SOURCESPS Technologies prides itself on ourcommitment to quality and our ability tomeet exacting specifications. Through amajor investment of equipment andtechnology, SPS has the capability tomanufacture these parts completely in-house and, for this primary reason, hasbeen named by Boeing as a D590 qualifiedsource for NAS 1351 and 1352 socket headcap screws. Don’t confuse these parts withstandard socket screws. They are moreexpensive because their processingrequirements are more comprehensive, dueto the critical nature of their use.

Don’t Jeopardize Your ReputationMake sure, when you are supplying theseparts that you know where they areultimately going to be used. Even when thepurchaser is a subcontractor, keep in mindthat the end use for these may be part of aBoeing assembly and therefore must besupplied by a manufacturer listed on theD590. If you or your customer are notcertain as to their end-use; you have apolicy decision to make.Drawings subject torevision. To assure you have currentdrawings contact SPS TechnologiesAerospace Product Engineering Dept. orreference the SPS Fastener Finder on ourweb site: www.spstech.com/aero.

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Recommended seating torqueslisted serve as guidelines only.Even when using the recommendedseating torques, the induced loadsobtained may vary as much as±25% depending upon theuncontrolled variables such asmating material, plating, lubrication,

surface finish, hardness, bolt/jointcompliance and method oftightening. The best way todetermine the correct torque is torun tests on the particular joint bytightening sample bolts until theyreach yield. The optimum torque is80% of this value.

SPS Technologies Socket Head Cap Screws

WARNING: Please use the following important informationwhen selecting fasteners from the following pages:

Products listed as Military Standards havebeen manufactured to meet or exceed thosestandards. To verify latest qualificationsstatus, contact SPS TechnologiesAerospace Fasteners Group CustomerService Department.

The products in this catalog have beendesigned and manufactured to perform to specific standards for the military/aerospace markets.

Reworking, modifying, plating or re-plating,altering or causing the same to be done on

any SPS product as manufactured, certifiedand supplied by SPS Technologies isprohibited. In the event that such action istaken, product cannot be represented asSPS product.

The standards contained herein takeprecedence over documents referencedherein. Referenced drawings, standards anddocuments shall be of the issue in effect on date of invitation to bid. Catalogdrawings and part numbers are for orderingpurposes only.

Socket Head Cap Screw, Hexagon Recess, Alloy and Stainless Steel 1960 Series

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DASH NO. THREAD SIZE ØA ØB E MIN. F MIN. H R FILLET EXT. W NOM..096 .060 .020 .025 .060 .007 .050

90 .060-80 UNRF-3A .091 .0568 .057 .00391 .073-64 UNRC-3A .118 .073 .025 .031 .073 .007 .062

.073-72 UNRF-3A .112 .0695 .070 .00392 .086-56 UNRC-3A .140 .086 .029 .038 .086 .008 .078

.086-64 UNRF-3A .134 .0822 .083 .00493 .099-48 UNRC-3A .161 .099 .034 .044 .099 .008 .078

.099-56 UNRF-3A .154 .0949 .095 .00494 .112-40 UNRC-3A .183 .112 .038 .051 .112 .009 .094

.112-48 UNRF-3A .176 .1075 .108 .00595 .125-40 UNRC-3A .205 .125 .043 .057 .125 .010 .094

.125-44 UNRF-3A .198 .1202 .121 .00696 .138-32 UNRC-3A .226 .138 .047 .064 .138 .010 .109

.138-40 UNRF-3A .218 .1329 .134 .00698 .164-32 UNRC-3A .270 .164 .056 .077 .164 .012 .141

.164-36 UNRF-3A .262 .1585 .159 .0073 .190-24 UNRC-3A .312 .190 .065 .090 .190 .014 .156

.190-32 UNRF-3A .303 .184 .185 .0094 .250-20 UNRC-3A .375 .250 .095 .120 .250 .014 .188

.250-28 UNRF-3A .365 .2435 .244 .0095 .312-18 UNRC-3A .469 .3125 .119 .151 .312 .017 .250

.312-24 UNRF-3A .457 .3053 .306 .0126 .375-16 UNRC-3A .562 .375 .143 .182 .375 .020 .312

.375-24 UNRF-3A .550 .3678 .368 .0157 .437-14 UNRC-3A .656 .4375 .166 .213 .438 .023 .375

.437-20 UNRF-3A .642 .4294 .430 .0188 .500-13 UNRC-3A .750 .500 .190 .245 .500 .026 .375

.500-20 UNRF-3A .735 .4919 .492 .0209 .562-12 UNRC-3A .843 .5625 .214 .265 .562 .028 .437

.562-18 UNRF-3A .827 .5538 .554 .02210 .625-11 UNRC-3A .938 .625 .238 .307 .625 .032 .500

.625-18 UNRF-3A .921 .6163 .616 .02412 .750-10 UNRC-3A 1.125 .750 .285 .370 .750 .039 .625

750-16 UNRF-3A 1.107 .7406 .740 .03014 .875-9 UNRC-3A 1.312 .875 .333 .432 .875 .044 .750

.875-14 UNRF-3A 1.293 .8647 .864 .03416 1.000-8 UNRC-3A

1.000-12 UNRF-3A 1.500 1.000 .380 .495 1.000 .050 .7501.000-14 UNRS-3A 1.479 .9886 .988 .040

18 1.125-7 UNRC-2A 1.688 1.125 .428 .557 1.125 .055 .8751.125-12 UNRF-2A 1.665 1.1086 1.111 .045

20 1.250-7 UNRC-2A 1.875 1.250 .475 .620 1.250 .060 .8751.250-12 UNRF-2A 1.852 1.2336 1.236 .050

22 1.375-6 UNRC-2A 2.062 1.375 .523 .682 1.375 .065 1.0001.375-12 UNRF-2A 2.038 1.3568 1.360 .055

24 1.500-6 UNRC-2A 2.250 1.500 .570 .745 1.500 .070 1.0001.500-12 UNRF-2A 2.224 1.4818 1.485 .060

28 1.750-5 UNRC-2A 2.625 1.750 .665 .870 1.750 .080 1.2501.750-12 UNRF-2A 2.597 1.7295 1.734 .070

32 2.000-4.5 UNRC-2A 3.000 2.000 .760 .995 2.000 .090 1.5002.000-12 UNRF-2A 2.970 1.9780 1.983 .075

36 2.250-4.5 UNRC-2A 3.375 2.250 .855 1.120 2.250 .100 1.7502.250-12 UNRF-2A 3.344 2.2280 2.232 .085

40 2.500-4 UNRC-2A 3.750 2.500 .950 1.245 2.500 .110 1.7502.500-12 UNRF-2A 3.717 2.4762 2.481 .095

44 2.750-4 UNRC-2A 4.125 2.750 1.045 1.370 2.750 .120 2.0002.750-12 UNRF-2A 4.090 2.7262 2.730 .105

48 3.000-4 UNRC-2A 4.500 3.000 1.140 1.495 3.000 .130 2.2503.000-12 UNRF-2A 4.464 2.9762 2.979 .115

LENGTH SEE PAGE 12-13

MARKINGSEE NOTE 4

CROSSDRILL HOLESWHEN SPECIFIEDSEE NOTE 5

SEE PAGE 12-13

SEE PAGE 12-13

LGMAX

H

ØA

ØB

WF F

E30°REF 45°

REF

E

R

LBMIN

OPTIONALMACHINESOCKET

STANDARDS AND SPECIFICATIONS: FF-S-86

Socket Head Cap Screw, Hexagon Recess, Alloy Steel, 1960 Series

SIZE TENSILE STRENGTH *RECOMMENDED SEATING ULTIMATE YIELD DOUBLE SHEARLBS. MIN. TORQUE IN INCH POUNDS TENSILE STRENGTH STRENGTH

PLAIN STRENGTH PSI PSI OF BODYUNRC UNRF UNRC UNRF MIN. MIN. LBS. MIN.

#0 — 340 — 2 190,000 170,000 640#1 500 530 4 4 190,000 170,000 950#2 700 750 6 7 190,000 170,000 1,320#3 930 1,000 10 11 190,000 170,000 1,750#4 1,150 1,260 15 16 190,000 170,000 2,240#5 1,510 1,580 20 21 190,000 170,000 2,800#6 1,730 1,930 28 30 190,000 170,000 3,400#8 2,660 2,800 49 50 190,000 170,000 4,800#10 3,330 3,800 64 76 190,000 170,000 6,4501/4 6,050 6,910 150 170 190,000 170,000 11,2005/16 9,960 11,000 305 325 190,000 170,000 17,5003/8 14,700 16,700 545 570 190,000 170,000 25,2007/16 20,200 22,600 840 900 190,000 170,000 34,2001/2 27,000 30,400 1,300 1,370 190,000 170,000 44,7009/16 32,800 36,500 1,860 1,970 180,000 155,000 53,7005/8 40,700 46,100 2,530 2,660 180,000 155,000 66,3003/4 60,200 67,100 4,400 4,800 180,000 155,000 95,4007/8 83,100 91,700 7,000 7,600 180,000 155,000 129,8001 109,000 119,000 10,400 11,000 180,000 155,000 169,6001(14) — 122,000 — 11,600 180,000 155,000 169,6001-1/8 137,000 154,000 14,900 16,600 180,000 155,000 214,0001-1/4 175,000 193,000 21,000 22,600 180,000 155,000 265,0001-3/8 208,000 237,000 27,800 29,300 180,000 155,000 320,0001-1/2 253,000 285,000 36,500 39,300 180,000 155,000 381,0001-3/4 342,000 394,000 59,900 68,900 180,000 155,000 519,0002 450,000 521,000 89,900 104,000 180,000 155,000 678,0002-1/4 585,000 664,000 131,000 150,000 180,000 155,000 858,0002-1/2 720,000 828,000 180,000 207,000 180,000 155,000 1,060,0002-3/4 888,000 1,006,000 244,000 277,000 180,000 155,000 1,282,0003 1,074,000 1,204,000 322,000 361,000 180,000 155,000 1,526,000

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*REFER TO WARNING ON PAGE 6.

TORQUE VALUES LISTED ARE FOR PLAIN SCREWS. FOR CADMIUM PLATED SCREWS, MULTIPLY RECOMMENDED SEATING TORQUE BY .75; FOR ZINC PLATEDSCREWS, MULTIPLY BY 1.40.

MECHANICAL PROPERTIES FOR ALLOY STEEL


MECHANICAL PROPERTIES FOR AUSTENITIC STAINLESS STEELSTANDARDS AND SPECIFICATIONS: FF-S-86

AUSTENITIC STAINLESS STEEL AUSTENITIC STAINLESS STEELSIZE TENSILE STRENGTH LBS. MIN. DOUBLE SHEAR STRENGTH OF BODY

UNRC UNRF LBS. MIN. #0 — 140 250#1 210 220 380#2 300 320 520#3 390 420 700#4 480 530 890#5 640 660 1,100#6 730 810 1,350#8 1,120 1,180 1,900#10 1,400 1,600 2,5501/4 2,540 2,910 4,4205/16 4,200 4,640 6,9003/8 6,200 7,020 9,9407/16 8,500 9,500 13,5001/2 11,400 12,800 17,7009/16 14,600 16,200 22,4005/8 18,100 20,500 27,6003/4 26,700 29,800 39,8007/8 37,000 40,700 54,1001 48,500 53,000 70,700

Socket Head Cap Screw, Hexagon Recess, 1960 Series

THE TENSILE STRENGTH IS BASED ON A STRESS OF 80 KSI AND THE AREA PER ASMEB1.1. THE SHEAR STRENGTH IS BASED ON A STRESS OF 45 KSI AND THE AREA AT NOMINAL “ØB.”

Socket Head Cap Screw, Hexagon Recess, Alloy and Stainless Steel 1960 Series

NOTE: Recommended seating torques for screws with cross drilled heads should be reduced by 25%.

APPLICABLE STANDARDS-MS 24673 thru 24678; NAS1351, 1352; Fed. Spec. FF-S-86, ASTM A574, ASME B18.3

SOCKET HEAD CAP SCREWS • 1960 SERIES CROSS DRILLED DATA

DIAMETER

9

A B P ALIGN-SCREW CROSS-DRILL HOLE MENT

SIZE LOCATION DIAMETER PLUGNOM. MAX. MIN. MAX. MIN. REF.

#2 .035 .025 .032 .026 .0210#3 .035 .025 .032 .026 .0210#4 .040 .026 .039 .033 .0280#5 .045 .030 .039 .033 .0280#6 .050 .035 .039 .033 .0280#8 .060 .040 .050 .044 .0340#10 .065 .045 .050 .044 .03401/4 .085 .065 .050 .044 .03405/16 .104 .084 .050 .044 .03403/8 .123 .103 .067 .061 .05107/16 .141 .121 .067 .061 .05101/2 .160 .140 .067 .061 .05109/16 .179 .159 .067 .061 .05105/8 .198 .178 .067 .061 .05103/4 .235 .215 .097 .091 .08107/8 .273 .253 .097 .091 .08101 .310 .290 .097 .091 .0810

1 1/8 .348 .328 .127 .119 .10401 1/4 .385 .365 .127 .119 .10401 3/8 .423 .403 .127 .119 .10401 1/2 .460 .440 .127 .119 .10401 5/8 .498 .478 .127 .119 .10401 3/4 .535 .515 .127 .119 .10401 7/8 .573 .553 .127 .119 .1040

2 .610 .590 .127 .119 .1040

1. BASIC PART NUMBERS: 94707 - ALLOY STEEL PER CHEMISTRY OF ASTM A574. HRC 38-43. MAGNETIC PARTICLE INSPECT PER ASTM E1444. ACCEPTANCE CRITERIA PER SPS-I-650.

94708 - AUSTENITIC STAINLESS STEEL PER CHEMISTRY OF ASTM A493. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650.

2. FINISH: REFER TO FINISH OPTIONS.3. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1. 4. MARK S OR SPS AS APPLICABLE.5. PART NUMBERING: ( ) ( ) ( ) – ( ) ( ) – ( ) ( ) FINISH OPTIONS:

FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.C-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (Alloy)NO LETTER-PASSIVATE (CRES) PER ASTM A967 OR EQUIVALENT.

= LENGTH IN SIXTEENTHSTHREAD = C-COARSE

F-FINES-SPECIAL

= DASH NUMBER (BASIC DIAMETER)LOCKING FEATURE = NO LETTER-NO LOCKING FEATURE

E-TYPE P (PATCH) PER MIL-DTL-18240 (250°F MAX)K-TYPE N (PELLET) PER MIL-DTL-18240 (250°F MAX)M-NYTEMP® PATCH (450°F MAX)TF-TRU-FLEX

CROSSDRILL HEADS=H1 - 1 HOLE THRUH2 - 2 HOLES THRUH3 - 3 HOLES THRU

BASIC PART NUMBER

DETAILS

DIA. #0 #1 #2 #3 #4 #5 #6 #8 #10 1/4 DASH NO. 90 91 92 93 94 95 96 98 3 4

DIA. 5/16 3/8 7/16 1/2 9/16 5/8 3/4 7/8 1 1-1/8DASH NO. 5 6 7 8 9 10 12 14 16 18

DIA. 1-1/4 1-3/8 1-1/2 1-3/4 2 2-1/4 2-1/2 2-3/4 3DASH NO. 20 22 24 28 32 36 40 44 48

R TENSILEDASH THREADS ØA ØB E F H FILLET T W STRENGTHNO. CLASS 3A MIN MIN EXT REF NOM LBS. MIN 256 .086-56 UNRC .104 .086 .029 .038 .086 .008 .625 .0781 590264 .086-64 UNRF .134 .0822 .083 .004 630348 .099-48 UNRC .161 .099 .034 .044 .099 .008 .625 .0781 780356 .099-56 UNRF .154 .0949 .095 .004 840440 .112-40 UNRC .183 .112 .038 .051 .112 .009 .750 .0937 970448 .112-48 UNRF .176 .1075 .108 .005 1,060540 .125-40 UNRC .205 .125 .043 .057 .125 .010 .750 .0937 1,270544 .125-44 UNRF .198 .1202 .121 .006 1,330632 .138-32 UNRC .226 .138 .047 .064 .138 .010 .750 .1093 1,450640 .138-40 UNRF .218 .1329 .134 .006 1,620832 .164-32 UNRC .270 .164 .056 .077 .164 .012 .875 .1406 2,240836 .164-36 UNRF .262 .1585 .159 .007 2,3601024 .190-24 UNRC .312 .190 .065 .090 .190 .014 .875 .1562 2,8001032 .190-32 UNRF .303 .184 .185 .009 3,200420 .250-20 UNRC .375 .250 .095 .120 .250 .014 1.000 .1875 5,090428 .250-28 UNRF .365 .2435 .244 .009 5,820518 .312-18 UNRC .469 .3125 .119 .151 .312 .017 1.125 .2500 8,380524 .312-24 UNRF .457 .3053 .306 .012 9,280616 .375-16 UNRC .562 .375 .143 .182 .375 .020 1.250 .3125 12,400624 .375-24 UNRF .550 .3678 .368 .015 14,000714 .437-14 UNRC .656 .4375 .166 .213 .438 .023 1.375 .3750 17,000720 .437-20 UNRF .642 .4294 .430 .018 19,000813 .500-13 UNRC .750 .500 .190 .245 .500 .026 1.500 .3750 22,700820 .500-20 UNRF .735 .4919 .492 .020 25,6001011 .625-11 UNRC .938 .625 .238 .307 .625 .032 1.750 .5000 36,2001018 .625-18 UNRF .921 .6163 .616 .024 41,0001210 .750-10 UNRC 1.125 .750 .285 .370 .750 .039 2.000 .6250 53,5001216 .750-16 UNRF 1.107 .7406 .740 .030 59,7001409 .875-9 UNRC 1.312 .875 .333 .432 .875 .044 2.250 .7500 73,9001414 .875-14 UNRF 1.293 .8647 .864 .034 81,5001608 1.000-8 UNRC 1.500 1.000 .380 .495 1.000 .050 2.500 .7500 96,9001612 1.000-12 UNRF 106,0001614 1.000-14 UNRS 1.479 .9886 .988 .040 109,0001807 1.125-7 UNRC 1.688 1.125 .428 .557 1.125 .055 2.812 .8750 122,0001812 1.125-12 UNRF 1.665 1.1086 1.111 .045 137,0002007 1.250-7 UNRC 1.875 1.250 .475 .620 1.250 .060 3.125 .8750 155,0002012 1.250-12 UNRF 1.852 1.2336 1.236 .050 171,0002206 1.375-6 UNRC 2.062 1.375 .523 .682 1.375 .065 3.437 1.0000 185,0002212 1.375-12 UNRF 2.038 1.3568 1.360 .055 210,0002406 1.500-6 UNRC 2.250 1.500 .570 .745 1.500 .070 3.750 1.0000 225,0002412 1.500-12 UNRF 2.224 1.4818 1.485 .060 253,000

10

LENGTH

THREADS PERASME B1.1

CROSSDRILL HEADS PER FF-S-86 WHEN SPECIFIED SEE NOTE 6

MAX TWO IMP THDS

MARK “KS1216“ ON TOP OR SIDE OF HEADOTHER IDENTIFICATION MARKINGS ATMANUFACTURER'S OPTION

H

ØA

ØB

WF

30°45°

E

TREF

R


Socket Head Cap Screw, Hexagon Recess, A286, 1960 Series

DIAMETER UP TO 1" OVER 1" TO OVER 2-1/2" OVER 6"INCL. 2-1/2" INCL. TO 6" INCL.

.086 THRU .375 -.030 -.040 -.060 -.1207/16 THRU 3/4 -.030 -.060 -.080 -.1207/8 THRU 1-1/8 -.050 -.100 -.140 -.200

MECHANICAL PROPERTIES AND SEATING TORQUES

LENGTH TOLERANCE

1. MATERIAL: A286 PER CHEMISTRY OF AMS 5731, AMS 5737 OR AMS 5853.2. HEAT TREAT: TO MEET THE MINIMUM ULTIMATE TENSILE REQUIREMENTS OF 160 KSI.3. MANUFACTURING REQUIREMENTS: HEAD SHALL BE FORGED.

SOCKET MAY BE FORGED OR MACHINED.THREADS TO BE ROLLED AFTER PRECIPITATION HEAT TREATMENT.

4. DIMENSIONS PER ASME B18. 3.5. PARTS LONGER THAN “T REF” WILL HAVE A MINIMUM THREAD LENGTH AS TABULATED ON PAGE 10.

PARTS EQUAL TO OR SHORTER THAN “T REF” WILL BE THREADED TO HEAD.6. PART NUMBERING: KS1216 ( ) - ( ) ( ) - ( ) ( ) FINISH OPTIONS:

FINISH = B - CHEMICAL BLACK OXIDE PER MIL-C-13924C - CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2D - CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3H - CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2J - CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2

(YELLOW CHROMATE)M - CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2

(OLIVE DRAB)S - SILVER PLATE PER AMS2410U - ZINC PLATE PER ASTM B633 TYPE III SC1Z - ZINC PLATE PER ASTM B633 TYPE II SC1NO LETTER - PASSIVATE PER AMS-QQ-P-35

= LENGTH IN SIXTEENTHS

CROSSDRILL HEADS = H1 - 1 HOLE THRUH2 - 2 HOLES THRUH3 - 3 HOLES THRU

DASH NUMBER PER TABULATION

LOCKING FEATURE = NO LETTER - NO LOCKING FEATUREE - TYPE P (PATCH) PER MIL-DTL-18240 (250°F MAX)K - TYPE N (PELLET) PER MIL-DTL-18240 (250°F MAX)M - NYTEMP PATCH (450°F MAX)TF - TRU-FLEX

BASIC PART NUMBER

NOM. BASIC TENSILE YIELD DOUBLE RECOM. SEATING SIZE SCREW STRENGTH STRENGTH SHEAR STR. TORQUES INCH-LBS.

DIAMETER PSI. MIN. PSI. MIN. OF BODYLBS. MIN. UNRC UNRF

#4 .112 160,000 120,000 1,770 15 17#5 .125 160,000 120,000 2,200 22 23#6 .138 160,000 120,000 2,700 28 31#8 .164 160,000 120,000 3,800 51 54#10 .190 160,000 120,000 5,100 75 851/4 .250 160,000 120,000 8,800 152 1745/16 .312 160,000 120,000 13,800 314 3473/8 .375 160,000 120,000 19,800 465 527

7/16 .437 160,000 120,000 27,000 743 8301/2 .500 160,000 120,000 35,300 1140 1,2805/8 .625 160,000 120,000 55,200 2260 2,5603/4 .750 160,000 120,000 79,500 4010 4,4807/8 .875 160,000 120,000 108,000 6460 7,1301 1.000 160,000 120,000 144,000 9690 10,600

11

Socket Head Cap Screw, Hexagon Recess, A286, 1960 Series


12

BODY AND GRIP LENGTHS FOR SOCKET HEAD CAP SCREWS

SIZE #0 #1 #2 #3 #4 #5 #6 #8 #10 1/4 NOM .

LENGTH LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB

3/4 .250 .190

7/8 .250 .190 .250 .170 .250 .160 .250 .150

1 .500 .440 .250 .170 .250 .160 .250 .150 .250 .120 .250 .120

1-1/4 .750 .690 .620 .550 .620 .540 .620 .520 .250 .120 .250 .120 .500 .340 .380 .220 .380 .170

1-1/2 .880 .800 .880 .790 .880 .770 .750 .620 .750 .620 .500 .340 .380 .220 .380 .170 .500 .250

1-3/4 1.120 1.040 1.120 1.020 .750 .620 .750 .620 1.000 .840 .880 .720 .880 .670 .500 .250

2 1.380 1.270 1.250 1.120 1.250 1.120 1.000 .840 .880 .720 .880 .670 1.000 .750

2-1/4 1.250 1.120 1.250 1.120 1.500 1.340 1.380 1.220 1.380 1.170 1.000 .750

2-1/2 1.750 1.620 1.500 1.340 1.380 1.220 1.380 1.170 1.500 1.250

2-3/4 2.000 1.840 1.880 1.720 1.880 1.670 1.500 1.250

3 1.880 1.720 1.880 1.670 2.000 1.750

3-1/4 2.380 2.220 2.380 2.170 2.000 1.750

3-1/2 2.380 2.170 2.500 2.250

3-3/4 2.880 2.670 2.500 2.250

4 2.880 2.670 3.000 2.750

4-1/4 3.000 2.750

4-1/2 3.500 3.250

4-3/4 3.500 3.250

5 4.000 3.750

5-1/4

5-1/2

5-3/4

6

6-1/4

6-1/2

6-3/4

7

7-1/4

7-1/2

7- 3/4

8

8-1/2

9

9-1/2

10

11

12

13

14

15

16

17

18

19

20

LENGTH

LGMAX

LBMIN

LT

LTT

LT LTT TOTALBASIC THREAD THREAD

THREAD LENGTH LENGTHDIAMETER MIN MAX

#0 0.50 0.62#1 0.62 0.77#2 0.62 0.80#3 0.62 0.83#4 0.75 0.99#5 0.75 1.00#6 0.75 1.05#8 0.88 1.19#10 0.88 1.271/4 1.00 1.505/16 1.12 1.713/8 1.25 1.947/16 1.38 2.171/2 1.50 2.385/8 1.75 2.823/4 2.00 3.257/8 2.25 3.691 2.50 4.12

1-1/8 2.81 4.651-1/4 3.12 5.091-3/8 3.44 5.651-1/2 3.75 6.081-3/4 4.38 7.13

2 5.00 8.112-1/4 5.62 8.992-1/2 6.25 10.002-3/4 6.88 10.87

3 7.50 11.75

THE LENGTH OF COMPLETE THREAD "LT" SHALL BE CONTROLLED BY THEGRIP LENGTH "LG" AS DESCRIBED IN NOTE A). AND THE LENGTH OF TOTALTHREAD "LTT" SHALL BE CONTROLLED BY THE BODY LENGTH "LB" AS SETFORTH IN NOTE B). THE "LT" MINIMUM AND "LTT" MAXIMUM VALUES SHOWNIN TABLE II ARE REFERENCE DIMENSIONS INTENDED FOR CALCULATIONPURPOSES ONLY IN ACCORDANCE WITH NOTE C). SEE SKETCH ABOVE.

A) THE GRIP LENGTH "LG" SHALL BE MAXIMUM AND REPRESENTS THEMINIMUM DESIGN GRIP LENGTH OF THE SCREW. IT SHALL BE MEASURED,PARALLEL TO THE AXIS OF SCREW, FROM THE BEARING SURFACE OF THEHEAD TO THE FACE OF A "GO" THREAD RING GAGE, HAVING THECOUNTERSINK AND/OR COUNTERBORE REMOVED, WHICH HAS BEENASSEMBLED BY HAND AS FAR AS THE THREAD WILL PERMIT. THE "LG"MAXIMUM LENGTH IS A CRITERION FOR ACCEPTANCE AND SHALLCONFORM TO THE VALUES GIVEN IN TABLE I OR, FOR DIAMETER/LENGTHCOMBINATIONS NOT SHOWN THEREIN, SHALL BE AS CALCULATED PER NOTE C).

B) THE BODY LENGTH "LB" SHALL BE MINIMUM AND REPRESENTS THEMINIMUM FULL BODY LENGTH OF THE SCREW. IT SHALL BE MEASURED,PARALLEL TO THE AXIS OF THE SCREW, FROM THE BEARING SURFACE OFTHE HEAD TO THE TOP OF THE EXTRUSION ANGLE OR TO THE LASTSCRATCH OF THE THREAD. THE "LB" MINIMUM LENGTH IS A CRITERION FORACCEPTANCE AND SHALL CONFORM TO THE VALUES GIVEN IN TABLE I OR,FOR DIAMETER/LENGTH COMBINATIONS NOT SHOWN THEREIN, SHALL BEAS CALCULATED IN ACCORDANCE WITH NOTE C).

C) FOR SCREWS OF THE NOMINAL LENGTH NOT LISTED IN TABLE I AND FORNOMINAL SIZES LARGER THAN 1 INCH DIAMETER, THE MAXIMUM GRIPLENGTH "LG" AND MINIMUM BODY LENGTH "LB" SHALL BE DETERMINEDFROM THE FOLLOWING FORMULAS:LG = LENGTH – LTLB = LENGTH – LTTWHERE: LENGTH = NOMINAL SCREW LENGTH; LT = MINIMUM THREADLENGTH FROM TABLE II; LTT = MAXIMUM TOTAL THREAD LENGTH FROMTABLE II.SCREWS HAVING NOMINAL LENGTH FALLING BETWEEN THOSE FOR WHICH"LG" AND "LB" VALUES ARE TABULATED IN TABLE II SHALL HAVE "LG" AND"LB" DIMENSIONS CONFORMING TO THOSE OF THE NEXT SHORTERTABULATED NOMINAL LENGTH FOR THE RESPECTIVE SCREW SIZE.

UP TO OVER 1" TO OVER 2-1/2" SIZE 1" INCL. 2-1/2" INCL. TO 6" INCL. OVER 6"

#0 THRU 3/8" -0.03 -0.04 -0.06 -0.127/16" THRU 3/4" -0.03 -0.06 -0.08 -0.127/8" AND 1-1/2" -0.05 -0.10 -0.14 -0.20

OVER 1-1/2" — -0.18 -0.20 -0.24

LENGTH TOLERANCE TABLE

TABLE I

TABLE II


13

FOR LENGTHS SHORTER THAN LISTED, SCREWS WILL BE THREADED AS CLOSE TO THE HEAD AS PRACTICABLE (APPROX. WITHIN 2 THREAD PITCHES).

STANDARDS AND SPECIFICATIONS: FF-S-865/16 3/8 7/16 1/2 9/16 5/8 3/4 7/8 1

LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB

.620 .350 .500 .190

.620 .350 .500 .190 .620 .270

1.120 .850 1.000 .690 .620 .270 .750 .360

1.120 .850 1.000 .690 1.120 .770 .750 .360 .870 .460

1.620 1.350 1.500 1.190 1.120 .770 .750 .360 .870 .460 .750 .300

1.620 1.350 1.500 1.190 1.620 1.270 1.500 1.120 .870 .460 .750 .300 1.000 .500

2.120 1.850 2.000 1.690 1.620 1.270 1.500 1.120 1.620 1.210 .750 .300 1.000 .500 1.000 .440

2.120 1.850 2.000 1.690 2.120 1.770 1.500 1.120 1.620 1.210 1.500 1.040 1.000 .500 1.000 .440 1.000 .380

2.620 2.350 2.500 2.190 2.120 1.770 2.250 1.860 1.620 1.210 1.500 1.040 1.000 .500 1.000 .440 1.000 .380

2.620 2.350 2.500 2.190 2.620 2.270 2.250 1.860 2.370 1.960 1.500 1.040 2.000 1.500 1.000 .440 1.000 .380

3.120 2.850 3.000 2.690 2.620 2.270 2.250 1.860 2.370 1.960 2.250 1.800 2.000 1.500 2.000 1.440 1.000 .380

3.120 2.850 3.000 2.690 3.120 2.770 3.000 2.620 2.370 1.960 2.250 1.800 2.000 1.500 2.000 1.440 2.000 1.380

3.620 3.350 3.500 3.190 3.120 2.770 3.000 2.620 3.120 2.710 2.250 1.800 2.000 1.500 2.000 1.440 2.000 1.380

3.620 3.350 3.500 3.190 3.620 3.270 3.000 2.620 3.120 2.710 3.000 2.540 3.000 2.500 2.000 1.440 2.000 1.380

4.120 3.850 4.000 3.690 3.620 3.270 3.750 3.360 3.120 2.710 3.000 2.540 3.000 2.500 3.000 2.440 2.000 1.380

4.120 3.850 4.000 3.690 4.120 3.770 3.750 3.360 3.870 3.460 3.000 2.540 3.000 2.500 3.000 2.440 3.000 2.380

4.620 4.350 4.500 4.190 4.120 3.770 3.750 3.360 3.870 3.460 3.750 3.300 3.000 2.500 3.000 2.440 3.000 2.380

4.620 4.350 4.500 4.190 4.620 4.270 4.500 4.120 3.870 3.460 3.750 3.300 4.000 3.500 3.000 2.440 3.000 2.380

5.120 4.850 5.000 4.690 4.620 4.270 4.500 4.120 4.620 4.210 3.750 3.300 4.000 3.500 4.000 3.440 3.000 2.380

5.000 4.690 5.120 4.770 4.500 4.120 4.620 4.210 4.500 4.040 4.000 3.500 4.000 3.440 4.000 3.380

5.500 5.190 5.120 4.770 5.250 4.860 4.620 4.210 4.500 4.040 4.000 3.500 4.000 3.440 4.000 3.380

5.500 5.190 5.620 5.270 5.250 4.860 5.370 4.960 4.500 4.040 5.000 4.500 4.000 3.440 4.000 3.380

6.000 5.690 5.620 5.270 5.250 4.860 5.370 4.960 5.250 4.800 5.000 4.500 5.000 4.440 4.000 3.380

6.000 5.690 6.120 5.770 6.000 5.620 5.370 4.960 5.250 4.800 5.000 4.500 5.000 4.440 5.000 4.380

6.120 5.770 6.000 5.620 6.120 5.710 5.250 4.800 5.000 4.500 5.000 4.440 5.000 4.380

6.620 6.270 6.000 5.620 6.120 5.710 6.000 5.540 6.000 5.500 5.000 4.440 5.000 4.380

7.120 6.270 7.000 6.620 6.870 6.460 6.000 5.540 6.000 5.500 6.000 5.440 6.000 5.380

7.620 7.270 7.000 6.620 6.870 6.460 6.750 6.300 7.000 6.500 6.000 5.440 6.000 5.380

8.000 7.620 7.620 7.210 6.750 6.300 7.000 6.500 7.000 6.440 7.000 6.380

8.000 7.620 7.620 7.210 7.750 7.300 8.000 7.500 7.000 6.440 7.000 6.380

9.120 8.710 7.750 7.300 9.000 8.500 8.000 7.440 8.000 7.380

10.120 9.710 9.250 8.800 10.000 9.500 9.000 8.440 9.000 8.380

10.250 9.800 11.000 10.500 10.000 9.440 10.000 9.380

12.000 11.500 11.000 10.440 11.000 10.380

13.000 12.500 12.000 11.440 12.000 11.380

13.000 12.440 13.000 12.380

14.000 13.440 14.000 13.380

15.000 14.440 15.000 14.380

16.000 15.380

17.000 16.380

TABLE I

Socket Head, Low Head Type, Alloy Steel - 170 KSI U.T.S., and A286 - 140 KSI U.T.S.

14

RTHREADS FILLET

DASH NOMINAL PER INCH CLASS ØA ØB F H EXTENSION WNO. DIAM. UNRC UNRF MAX./MIN. MAX./MIN. MIN. MAX.MIN. MAX./MIN. NOM.

-94 #4 40 48 3A .183/.178 .1120/.1075 .038 .059/.053 .009/.005 .0500

-95 #5 40 44 3A .205/.200 .1250/.1202 .044 .065/.059 .010/.006 .0625

-96 #6 32 40 3A .226/.221 .1380/.1329 .050 .072/.066 .010/.006 .0625

-98 #8 32 36 3A .270/.265 .1640/.1585 .060 .085/.079 .012/.007 .0781

-3 #10 24 32 3A .312/.307 .1900/.1840 .072 .098/.092 .014/.009 .0938

-4 1/4 20 28 3A .375/.369 .2500/.2435 .094 .127/.121 .014/.009 .1250

-5 5/16 18 24 3A .437/.431 .3125/.3053 .110 .158/.152 .017/.012 .1562

-6 3/8 16 24 3A .562/.556 .3750/.3678 .115 .192/.182 .020/.015 .1875

-8 1/2 13 20 3A .750/.743 .5000/.4919 .151 .254/.244 .026/.020 .2500

-10 5/8 11 18 3A .938/.921 .6250/.6163 .225 .316/.306 .032/.024 .3125

-12 3/4 10 16 3A 1.125/1.107 .7500/.7406 .247 .376/.366 .039/.030 .3750

-14 7/8 9 14 3A 1.312/1.293 .8750/.8647 .304 .438/.428 .044/.034 .5000

-16 1 8 12 3A 1.500/1.479 1.0000/.9886 .359 .500/.489 .050/.040 .5620

-18 1-1/8 7 12 3A 1.6888/1.665 1.1250/1.1086 .396 .565/.554 .055/.045 .6250

MARK S OR SPS AS APPLICABLE

CHAMFER OR RADIUS

CHAMFER TOBELOW ROOTOF THREAD

15

Socket Head Cap Screw, Low Head Type

DIAMETER TO 1" OVER 1" TO 2.5" OVER 2.5"ALL -.03 -.04 -.06


(a) THE MINIMUM USABLE THREAD LENGTH SHALL BE EQUAL TO TWO TIMES THE NOMINAL DIAMETER + .500 INCH. FOR GRIP LENGTHS, SEE TABLE ON NEXT PAGE.(b) IMPERFECT THREADS NOT TO ENTER INTO FILLET AREA.


95299 - A286 PER CHEMISTRY OF AMS 5731, AMS 5737 OR AMS 5853 - 160 KSI. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650.

2. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1. 3. FINISH: REFER TO FINISH OPTIONS.4. MANUFACTURING REQUIREMENTS: HEAD TO BE FORGED.

SOCKET MAY BE FORGED OR MACHINED.THREADS TO BE ROLLED.

5. PART NUMBERING: ( ) ( ) – ( ) ( ) – ( ) ( ) FINISH OPTIONS:FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.

C-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)N-NICKEL CADMIUM PLATE PER AMS2416.S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (ALLOY)NO LETTER-PASSIVATE (CRES)


F-FINE

= DASH NUMBER (PER TABULATION)LOCKING FEATURE = NO LETTER-NO LOCKING FEATURE

E-TYPE P (PATCH) PER MIL-DTL-18240 (250°F MAX)K-TYPE N (PELLET) PER MIL-DTL-18240 (250°F MAX)M-NYTEMP PATCH (450°F MAX)TF-TRU-FLEX

BASIC PART NUMBER

Socket Head Cap Bolt, Low Head Type

16

BODY AND GRIP LENGTHS FOR SOCKET HEAD CAP SCREWS, LOW HEAD TYPEFOR LENGTHS SHORTER THAN LISTED, SCREWS WILL BE THREADED TO WITHIN 2-1/2 THREAD PITCHES OF THE HEAD.

SIZE #4 #5 #6 #8 #10 1/4 NOM .LENGTH LG LB LG LB LG LB LG LB LG LB LG LB

1-1/4 0.500 0.380 0.500 0.380 0.500 0.340 0.380 0.220

1-1/2 0.500 0.380 0.500 0.380 0.500 0.340 0.380 0.220 0.620 0.420

1-3/4 1.000 0.880 1.000 0.880 1.000 0.840 0.880 0.720 0.620 0.420 0.750 0.500

2 1.000 0.880 1.000 0.880 1.000 0.840 0.880 0.720 1.120 0.920 0.750 0.500

2-1/4 1.500 1.380 1.500 1.380 1.500 1.340 1.380 1.220 1.120 0.920 1.250 1.000

2-1/2 1.500 1.340 1.380 1.220 1.620 1.420 1.250 1.000

2-3/4 2.000 1.840 1.880 1.720 1.620 1.420 1.750 1.500

3 1.880 1.720 2.120 1.920 1.750 1.500

3-1/4 2.380 2.222 2.120 1.920 2.250 2.000

3-1/2 2.620 2.420 2.250 2.000

3-3/4 2.620 2.420 2.750 2.500

4 3.120 2.920 2.750 2.500

4-1/4 3.250 3.000

4-1/2 3.250 3.000

4-3/4 3.750 3.500

5 3.750 3.500

5-1/4 4.250 4.000

5-1/2

5-3/4

6

6-1/4

6-1/2

6-3/4

7

7-1/4

7-1/2

7-3/4

8

8-1/2

9

9-1/2

10

11

12

13

14

15

16

17

18

19

20

Socket Head Cap Bolt, Low Head Type

17

5/16 3/8 1/2 5/8 3/4 7/8 1

LG LB LG LB LG LB LG LB LG LB LG LB LG LB

0.880 0.600

0.880 0.600 1.000 0.690

1.380 1.100 1.000 0.690 1.000 0.620

1.380 1.100 1.500 1.190 1.000 0.620

1.880 1.600 1.500 1.190 1.000 0.620

1.880 1.600 2.000 1.690 1.750 1.360 1.500 1.040

2.380 2.100 2.000 1.690 1.750 1.360 1.500 1.040 1.500 1.000

2.380 2.100 2.500 2.190 1.750 1.360 1.500 1.040 1.500 1.000 1.500 0.940

2.880 2.600 2.500 2.190 2.500 2.120 2.250 1.800 1.500 1.000 1.500 0.940 1.500 0.880

2.880 2.600 3.000 2.690 2.500 2.120 2.250 1.800 1.500 1.000 1.500 0.940 1.500 0.880

3.380 3.100 3.000 2.690 2.500 2.120 2.250 1.800 2.500 2.000 1.500 0.940 1.500 0.880

3.380 3.100 3.500 3.190 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 1.500 0.880

3.880 3.600 3.500 3.190 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 2.500 1.880

3.880 3.600 4.000 3.690 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 2.500 1.880

4.380 4.100 4.000 3.690 4.000 3.620 3.750 3.300 3.500 3.000 2.500 1.940 2.500 1.880

4.380 4.100 4.500 4.190 4.000 3.620 3.750 3.300 3.500 3.000 3.500 2.940 2.500 1.880

4.880 4.600 4.500 4.190 4.000 3.620 3.750 3.300 3.500 3.000 3.500 2.940 3.500 2.880

4.880 4.600 5.000 4.690 4.750 4.360 4.500 4.040 3.500 3.000 3.500 2.940 3.500 2.880

5.380 5.100 5.000 4.690 4.750 4.360 4.500 4.040 4.500 4.000 3.500 2.940 3.500 2.880

5.500 5.190 4.750 4.360 4.500 4.040 4.500 4.000 4.500 3.940 3.500 2.880

5.500 5.190 5.500 5.120 5.250 4.800 4.500 4.000 4.500 3.940 4.500 3.880

6.000 5.690 5.500 5.120 5.250 4.800 4.500 4.000 4.500 3.940 4.500 3.880

6.000 5.690 5.500 5.120 5.250 4.800 5.500 5.000 4.500 3.940 4.500 3.880

6.500 6.190 6.250 5.860 6.000 5.540 5.500 5.000 5.500 4.940 4.500 3.880

6.250 5.860 6.000 5.540 5.500 5.000 5.500 4.940 5.500 4.880

7.000 6.620 6.750 6.300 6.500 6.000 5.500 4.940 5.500 4.880

7.000 6.620 6.750 6.300 6.500 6.000 6.750 6.190 6.500 5.880

8.000 7.620 7.750 7.300 7.500 7.000 6.750 6.190 6.500 5.880

8.000 7.620 7.750 7.300 7.500 7.000 7.750 7.190 7.500 6.880

9.250 8.800 9.000 8.500 8.750 8.190 8.500 7.880

10.250 9.800 10.000 9.500 9.750 9.190 9.500 8.880

11.000 10.500 10.750 10.190 10.500 9.880

12.000 11.500 11.750 11.190 11.500 10.880

13.000 12.500 12.750 12.190 12.500 11.880

13.750 13.190 13.500 12.880

14.750 14.190 14.500 13.880

15.750 15.190 15.500 14.880

16.500 15.880

17.500 16.880

Button Head Screw, Hexagon Recess, Alloy Steel, 160 KSI U.T.S., and AusteniticStainless Steel, 80 KSI U.T.S.

18

DASH SIZE THREAD DESIGNATION ØA ØB F H L Q R SNO. UNRF CLASS UNRC CLASS MAX. MIN. MAX. MIN. MIN. MAX. MIN. (a) REF. REF. MAX. MIN.90 #0 .060-80 3A .114 .104 .060 .0568 .020 .032 .026 .500 .010 .070 .010 .00591 #1 .073-72 3A .073-64 3A .139 .129 .073 .0695 .028 .039 .033 .500 .010 .080 .010 .00592 #2 .086-64 3A .086-56 3A .164 .154 .086 .0822 .028 .046 .038 .500 .010 .099 .010 .00593 #3 .099-56 3A .099-48 3A .188 .176 .099 .0949 .035 .052 .044 .500 .010 .110 .010 .00594 #4 .112-48 3A .112-40 3A .213 .201 .112 .1075 .035 .059 .051 .500 .015 .135 .010 .00595 #5 .125-44 3A .125-40 3A .238 .226 .125 .1202 .044 .066 .058 .500 .015 .141 .010 .00596 #6 .138-40 3A .138-32 3A .262 .250 .138 .1329 .044 .073 .063 .625 .015 .158 .010 .00598 #8 .164-36 3A .164-32 3A .312 .298 .164 .1585 .052 .087 .077 .750 .015 .185 .015 .0103 #10 .190-32 3A .190-24 3A .361 .347 .190 .1840 .070 .101 .091 1.000 .020 .213 .015 .0104 1/4" .250-28 3A .250-20 3A .437 .419 .250 .2435 .087 .132 .122 1.000 .031 .249 .020 .0155 5/16" .312-24 3A .312-18 3A .547 .527 .3125 .3053 .105 .166 .152 1.000 .031 .309 .020 .0156 3/8" .375-24 3A .375-16 3A .656 .636 .375 .3678 .122 .199 .185 1.250 .031 .368 .020 .0158 1/2" .500-20 3A .500-13 3A .875 .851 .500 .4919 .175 .265 .245 2.000 .046 .481 .030 .02010 5/8" .625-18 3A .625-11 3A 1.000 .970 .625 .6163 .210 .331 .311 2.000 .062 .523 .030 .020

TENSILE STRENGTH *RECOMMENDED SEATING TORQUE DOUBLE SHEAR SIZE LBS. MIN. IN INCH POUNDS PLAIN (c) STRENGTH OF BODY W X

UNRC UNRF UNRC UNRF LBS. MIN. NOM. (d)#0 — 270 — 1.5 540 .035 .005#1 390 390 2.5 2.5 800 .050 .005#2 560 560 4.5 4.5 1,110 .050 .005#3 730 730 7.0 7.0 1,480 .0625 .005#4 970 1,060 8.0 8.0 1,890 .0625 .005#5 1,270 1,330 12.0 13.0 2,360 .0781 .005#6 1,450 1,620 15.0 17.0 2,880 .0781 .005#8 2,240 2,360 30.0 31.0 4,060 .0937 .006#10 2,800 3,200 40.0 45.0 5,440 .1250 .0071/4" 5,090 5,820 100.0 110.0 9,420 .1562 .0095/16" 8,380 9,280 200.0 220.0 14,720 .1875 .0113/8" 12,400 14,000 350.0 400.0 21,200 .2187 .0131/2" 22,700 25,600 850.0 1,000.0 37,700 .3125 .0185/8" 36,200 41,000 1,700.0 1,900.0 58,900 .3750 .021

(a) SCREW LENGTHS EQUAL TO OR SHORTER THAN LISTED IN COLUMN “L” WILL BETHREADED TO HEAD. FOR SCREWS LONGER THAN LISTED, THE MINIMUM USABLE THREADLENGTH SHALL EQUAL TWICE THE DIAMETER + .500 INCH. (b) IMPERFECT THREADS NOT TO ENTER INTO FILLET AREA.

(c) TORQUE VALUES LISTED ARE FOR PLAIN SCREWS. FOR CADMIUM PLATED SCREWS, MULTIPLY RECOMMENDED SEATING TORQUE BY . 75; FOR ZINC PLATED SCREWS, MULTIPLY BY 1.40.(d) RUNOUT- SOCKET TO BODY WITHIN ”X” T.I.R.


UP TO 1" INCL. OVER 1" TO 2" INCL. OVER 2"-.03 -.04 -.06


MECHANICAL PROPERTIES - ALLOY STEEL BUTTON HEAD SOCKET SCREW



SLIGHT FLAT OF CHAMFERPERMISSIBLE

MARK S OR SPS AS APPLICABLE

CHAMFER TOBELOW ROOT OF THREAD

OPTIONALMACHINESOCKET

Button Head Screw, Hexagon Recess

19

1. BASIC PART NUMBERS: 94702 - ALLOY STEEL PER CHEMISTRY OF ASTM A574. HRC 38-43 — 160 KSI. MAGNETIC PARTICLE INSPECT PER ASTM E1444. ACCEPTANCE CRITERIA PER SPS-I-650.

94703 - AUSTENITIC STAINLESS STEEL PER CHEMISTRY OF ASTM A493. 80 KSI. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650.

2. FINISH: REFER TO FINISH OPTIONS.3. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1.4. PART NUMBERING: ( ) ( ) – ( ) ( ) – ( ) ( ) FINISH OPTIONS:

FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.C-CADMIUM PLATE PER QQ-P-416. TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (ALLOY)NO LETTER-PASSIVATE (CRES)


F-FINE



BASIC PART NUMBER

TENSILE STRENGTH *RECOMMENDED SEATING DOUBLE SHEARSIZE LBS. MIN. TORQUE IN INCH POUNDS STRENGTH W X

(c) PLAIN (d) OF BODY NOM. (e)UNRC UNRF UNRC UNRF LBS. MIN.

#0 — 100 — 1.0 260 .035 .005#1 150 160 1.7 1.8 380 .050 .005#2 210 220 2.8 3.0 520 .050 .005#3 270 290 4.3 4.5 700 .0625 .005#4 340 370 6.0 6.6 880 .0625 .005#5 450 470 8.9 9.3 1,100 .0781 .005#6 510 570 11.0 12.0 1,340 .0781 .005#8 790 830 20.0 21.0 1,900 .0937 .006#10 980 1,120 30.0 34.0 2,560 .1250 .0071/4" 1,780 2,040 71.0 81.0 4,400 .1562 .0095/16" 2,940 3,250 123.0 136.0 6,900 .1875 .0113/8" 4,340 4,920 218.0 247.0 9,940 .2187 .0131/2" 7,950 8,950 532.0 600.0 17,680 .3125 .0185/8" 12,700 14,300 1,060.0 1,200.0 27,600 .3750 .021

MECHANICAL PROPERTIES - AUSTENITIC STAINLESS STEEL, BUTTON HEAD SOCKET SCREW

(c) THE TENSILE STRENGTH IS BASED ON 56 KSI AND THE TENSILE STRESS AREA PER ASMEB1.1.(d) TORQUE VALUES LISTED ARE FOR PLAIN SCREWS. FOR CADMIUM PLATED SCREWS, MULTIPLY RECOMMENDED SEATING TORQUE BY . 75; FOR ZINC PLATED SCREWS,MULTIPLY BY 1.40.(e) RUNOUT- SOCKET TO BODY WITHIN ”X” T.I.R.



82° Flat Head Screw, Hexagon Recess, Alloy Steel, 160 KSI U.T.S. and AusteniticStainless Steel, 80 KSI U.T.S.

20

DASH SIZE THREAD DESIGNATION ØA ØB F ØG H N Q R WNO. UNRF CLASS UNRC CLASS MAX.(a) MIN.(b) MAX. MIN. MIN. REF. REF. MAX. MIN. MAX. MAX. NOM.90 #0 .060-80 3A .138 .117 .060 .0568 .025 .0812 .044 .032 .027 .011 .006 .03591 #1 .073-72 3A .073-64 3A .168 .143 .073 .0695 .031 .0942 .054 .042 .035 .014 .008 .05092 #2 .086-64 3A .086-56 3A .197 .168 .086 .0822 .038 .1234 .064 .041 .034 .015 .010 .05093 #3 .099-56 3A .099-48 3A .226 .193 .099 .0949 .044 .1444 .073 .046 .037 .018 .010 .062594 #4 .112-48 3A .112-40 3A .255 .218 .112 .1075 .055 .1652 .083 .051 .041 .021 .012 .062595 #5 .125-44 3A .125-40 3A .281 .240 .125 .1202 .061 .1795 .090 .057 .046 .022 .014 .078196 #6 .138-40 3A .138-32 3A .307 .263 .138 .1329 .066 .1985 .097 .061 .049 .024 .015 .078198 #8 .164-36 3A .164-32 3A .359 .311 .164 .1585 .076 .2400 .112 .067 .055 .026 .015 .09373 #10 .190-32 3A .190-24 3A .411 .359 .190 .1840 .087 .2440 .127 .095 .081 .028 .015 .12504 1/4" .250-28 3A .250-20 3A .531 .480 .250 .2435 .111 .3314 .161 .113 .099 .029 .015 .15625 5/16" .312-24 3A .312-18 3A .656 .600 .3125 .3053 .135 .4047 .198 .143 .128 .031 .015 .18756 3/8" .375-24 3A .375-16 3A .781 .720 .375 .3678 .159 .4854 .234 .168 .152 .033 .015 .21877 7/16" .437-20 3A .437-14 3A .844 .781 .4375 .4294 .159 .5698 .234 .155 .140 .034 .015 .25008 1/2" .500-20 3A .500-13 3A .938 .872 .500 .4919 .172 .6500 .251 .162 .147 .034 .015 .31259 9/16" .562-18 3A .562-12 3A 1.063 .993 .5625 .5560 .220 .7200 .288 .194 .177 .036 .015 .312510 5/8" .625-18 3A .625-11 3A 1.188 1.112 .625 .6163 .220 .8012 .324 .219 .201 .040 .015 .375012 3/4" .750-16 3A .750-10 3A 1.438 1.355 .750 .7406 .220 1.1100 .396 .181 .165 .040 .015 .500014 7/8" .875-14 3A .875-9 3A 1.688 1.604 .875 .8647 .248 1.2896 .468 .221 .206 .040 .015 .562016 1" 1.000-12 3A 1.000-8 3A 1.938 1.841 1.0000 .9886 .297 1.4682 .540 .260 .246 .040 .015 .625018 1-1/8" 1.125-12 2A 1.125-7 2A 2.188 2.079 1.1250 1.1086 .325 1.6250 .611 .336 .319 .040 .031 .75020 1-1/4" 1.250-12 2A 1.250-7 2A 2.438 2.316 1.2500 1.2336 .358 1.6250 .683 .484 .464 .040 .031 .87522 1-3/8" 1.375-12 2A 1.375-6 2A 2.688 2.553 1.3750 1.3568 .402 1.8026 .755 .510 .485 .040 .031 .87524 1-1/2" 1.500-12 2A 1.500-6 2A 2.938 2.791 1.5000 1.4818 .435 2.1870 .827 .417 .387 .040 .031 1.000

UP TO OVER 1" TO OVER 2-1/2" SIZE 1" INCL. 2-1/2" INCL. TO 6" INCL. OVER 6"

#0 THRU 3/8" -.03 -.04 -.06 -.127/16" THRU 3/4" -.03 -.06 -.08 -.12

7/8" AND UP -.05 -.10 -.14 -.20

(a) Maximum - To theoretical sharp corners. (b) Minimum - Absolute with a flat.



SEE NOTE 5

LGSEE NOTE 4

SEE LENGTHTOLERANCE TABLEAND NOTE 4

LGSEE NOTE 4

82° Flat Head Screw, Hexagon Recess, Alloy Steel, 160 KSI U.T.S., and AusteniticStainless Steel, 80 KSI U.T.S.

21

(c) TORQUE VALUES LISTED ARE FOR PLAIN SCREWS. FOR CADMIUM PLATED SCREWS, MULTIPLY RECOMMENDED SEATING TORQUE BY .75; FOR ZINC PLATED SCREWS, MULTIPLY BY 1.40.(d) RUNOUT - SOCKET TO BODY WITHIN “X” T.I.R.(e) THE TENSILE STRENGTH IS BASED ON 56KSI AND THE TENSILE STRESS AREA PER ASMEB1.1


MECHANICAL PROPERTIES - ALLOY STEEL AND AUSTENITIC STAINLESS STEEL

1. BASIC PART NUMBERS: 94700 - ALLOY STEEL PER CHEMISTRY OF ASTM A574. HRC 36-43 — 160 KSI. MAGNETIC PARTICLE INSPECT PER ASTM E1444. ACCEPTANCE CRITERIA PER SPS-I-650.

94701 - AUSTENITIC STAINLESS STEEL PER CHEMISTRY OF ASTM A493 — 56 KSI U.T.S.. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650.

2. FINISH: REFER TO FINISH OPTIONS.3. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1. 4. THREAD LENGTHS: THE MINIMUM USABLE THREAD LENGTH SHALL BE EQUAL TO TWO TIMES THE NOMINAL DIAMETER +.500 INCH. FOR GRIP LENGTHS, SEE TABLE PP 22-23.5. MARK S OR SPS AS APPLICABLE.6. PART NUMBERING: ( ) ( ) – ( ) ( ) – ( ) ( )

FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.C-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (ALLOY)NO LETTER-PASSIVATE (CRES)


F-FINE



BASIC PART NUMBER

A L L O Y S T E E L A U S T E N I T I C S TA I N L E S S S T E E L*RECOMMENDED *RECOMMENDED

TENSILE STRENGTH SEATING TORQUE DOUBLE SHEAR TENSILE STRENGTH SEATING TORQUE DOUBLE SHEARSIZE X LBS. MIN. IN INCH POUNDS STRENGTH LBS. MIN. IN INCH POUNDS STRENGTH

(d) PLAIN (c) OF BODY (e) PLAIN (c) OF BODYUNRC UNRF UNRC UNRF LBS. MIN. UNRC UNRF UNRC UNRF LBS. MIN.

#0 0.005 — 270 — 1.5 540 — 100 — 1.0 260#1 0.005 390 390 2.5 2.5 800 150 160 1.7 1.8 380#2 0.005 560 560 4.5 4.5 1,110 210 220 2.8 3.0 520#3 0.005 730 730 7 7 1,480 270 290 4.3 4.5 700#4 0.005 970 1,060 8 8 1,890 340 370 6.0 6.6 880#5 0.005 1270 1,330 12 13 2,360 450 470 8.9 9.3 1,100#6 0.005 1450 1,620 15 17 2,880 510 570 11.0 12.0 1,340#8 0.006 2,240 2,360 30 31 4,060 790 830 20.0 21.0 1,900#10 0.007 2,800 3,200 40 45 5,440 980 1,120 30.0 34.0 2,5601/4" 0.009 5,090 5,820 100 110 9,420 1,780 2,040 71.0 81.0 4,4005/16" 0.011 8,380 9,280 200 220 14,720 2,940 3,250 123.0 136.0 6,9003/8" 0.013 12,400 14,000 350 400 21,200 4,390 4,920 218.0 247.0 9,9407/16" 0.015 17,000 19,000 560 625 28,800 5,950 6,650 349.0 388.0 13,5201/2" 0.018 22,700 25,600 850 1,000.00 37,700 7,950 8,950 532.0 600.0 17,6809/16" 0.019 29,100 32,500 1,200.00 1,360.00 47,800 10,200 11,400 767.0 856.0 22,4005/8" 0.021 36,200 41,000 1,700.00 1,900.00 58,900 12,700 14,300 1,060.0 1,200.0 27,6003/4" 0.026 53,400 59,700 3,000.00 3,200.00 84,800 18,700 20,900 1,880.0 2,100.0 39,8007/8" 0.030 73,900 81,400 5,000.00 5,400.00 115,400 25,900 28,500 3,030.0 3,340.0 54,2001" 0.035 97,000 106,000 7,200.00 7,600.00 150,800 33,900 37,100 4,550.0 5,000.0 70,600

1-1/8" 0.035 122,000 137,000 9,700.00 10,800.00 191,0001-1/4" 0.038 155,000 172,000 13,600.00 14,700.00 236,0001-3/8" 0.041 185,000 210,000 18,100.00 19,000.00 285,0001-1/2" 0.045 225,000 253,000 23,700.00 25,600.00 339,000


Button Head and 82° Flat Head Screw, Hexagon Recess, All Materials

22

SIZE #0 #1 #2 #3 #4 #5 #6 #8 #10 1/4 NOM. LENGTH LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB

3/4 0.250 0.190

7/8 0.250 0.190 0.250 0.170 0.250 0.160 0.250 0.150

1 0.500 0.440 0.250 0.170 0.250 0.160 0.250 0.150

1-1/4 0.750 0.690 0.620 0.550 0.620 0.540 0.620 0.520 0.500 0.380 0.500 0.380 0.500 0.340 0.380 0.220

1-1/2 0.880 0.800 0.880 0.790 0.880 0.770 0.500 0.380 0.500 0.380 0.500 0.340 0.380 0.220 0.620 0.420

1-3/4 1.120 1.040 1.120 1.020 1.000 0.880 1.000 0.880 1.000 0.840 0.880 0.720 0.620 0.420 0.750 0.500

2 1.380 1.270 1.000 0.880 1.000 0.880 1.000 0.840 0.880 0.720 1.120 0.920 0.750 0.500

2-1/4 1.500 1.380 1.500 1.380 1.500 1.340 1.380 1.220 1.120 0.920 1.250 1.000

2-1/2 1.500 1.340 1.380 1.220 1.620 1.420 1.250 1.000

2-3/4 2.000 1.840 1.880 1.720 1.620 1.420 1.750 1.500

3 1.880 1.720 2.120 1.920 1.750 1.500

3-1/4 2.380 2.222 2.120 1.920 2.250 2.000

3-1/2 2.620 2.420 2.250 2.000

3-3/4 2.620 2.420 2.750 2.500

4 3.120 2.920 2.750 2.500

4-1/4 3.250 3.000

4-1/2 3.250 3.000

4-3/4 3.750 3.500

5 3.750 3.500

5-1/4 4.250 4.000

5-1/2

5-3/4

6

6-1/4

6-1/2

6-3/4

7

7-1/4

7-1/2

7-3/4

8

8-1/2

9

9-1/2

10

11

12

13

14

15

16

17

18

19

20

BODY AND GRIP LENGTHS FOR FLAT HEAD SOCKET SCREWS

23

Button Head and 82° Flat Head Screw, Hexagon Recess, All Materials

5/16 3/8 7/16 1/2 5/8 3/4 7/8 1

LG LB LG LB LG LB LG LB LG LB LG LB LG LB LG LB

0.880 0.600

0.880 0.600 1.000 0.690

1.380 1.100 1.000 0.690 1.120 0.770 1.000 0.620

1.380 1.100 1.500 1.190 1.120 0.770 1.000 0.620

1.880 1.600 1.500 1.190 1.620 1.270 1.000 0.620

1.880 1.600 2.000 1.690 1.620 1.270 1.750 1.360 1.500 1.040

2.380 2.100 2.000 1.690 2.120 1.770 1.750 1.360 1.500 1.040 1.500 1.000

2.380 2.100 2.500 2.190 2.120 1.770 1.750 1.360 1.500 1.040 1.500 1.000 1.500 0.940

2.880 2.600 2.500 2.190 2.620 2.270 2.500 2.120 2.250 1.800 1.500 1.000 1.500 0.940 1.500 0.880

2.880 2.600 3.000 2.690 2.620 2.270 2.500 2.120 2.250 1.800 1.500 1.000 1.500 0.940 1.500 0.880

3.380 3.100 3.000 2.690 3.120 2.770 2.500 2.120 2.250 1.800 2.500 2.000 1.500 0.940 1.500 0.880

3.380 3.100 3.500 3.190 3.120 2.770 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 1.500 0.880

3.880 3.600 3.500 3.190 3.620 3.270 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 2.500 1.880

3.880 3.600 4.000 3.690 3.620 3.270 3.250 2.860 3.000 2.540 2.500 2.000 2.500 1.940 2.500 1.880

4.380 4.100 4.000 3.690 4.120 3.770 4.000 3.620 3.750 3.300 3.500 3.000 2.500 1.940 2.500 1.880

4.380 4.100 4.500 4.190 4.120 3.770 4.000 3.620 3.750 3.300 3.500 3.000 3.500 2.940 2.500 1.880

4.880 4.600 4.500 4.190 4.620 4.270 4.000 3.620 3.750 3.300 3.500 3.000 3.500 2.940 3.500 2.880

4.880 4.600 5.000 4.690 4.620 4.270 4.750 4.360 4.500 4.040 3.500 3.000 3.500 2.940 3.500 2.880

5.380 5.100 5.000 4.690 5.120 4.770 4.750 4.360 4.500 4.040 4.500 4.000 3.500 2.940 3.500 2.880

5.500 5.190 5.120 4.770 4.750 4.360 4.500 4.040 4.500 4.000 4.500 3.940 3.500 2.880

5.500 5.190 5.620 5.270 5.500 5.120 5.250 4.800 4.500 4.000 4.500 3.940 4.500 3.880

6.000 5.690 5.620 5.270 5.500 5.120 5.250 4.800 4.500 4.000 4.500 3.940 4.500 3.880

6.000 5.690 6.120 5.770 5.500 5.120 5.250 4.800 5.500 5.000 4.500 3.940 4.500 3.880

6.500 6.190 6.120 5.770 6.250 5.860 6.000 5.540 5.500 5.000 5.500 4.940 4.500 3.880

6.620 6.270 6.250 5.860 6.000 5.540 5.500 5.000 5.500 4.940 5.500 4.880

7.120 6.770 7.000 6.620 6.750 6.300 6.500 6.000 5.500 4.940 5.500 4.880

7.620 7.270 7.000 6.620 6.750 6.300 6.500 6.000 6.750 6.190 6.500 5.880

8.120 7.770 8.000 7.620 7.750 7.300 7.500 7.000 6.750 6.190 6.500 5.880

8.000 7.620 7.750 7.300 7.500 7.000 7.750 7.190 7.500 6.880

9.250 8.800 9.000 8.500 8.750 8.190 8.500 7.880

10.250 9.800 10.000 9.500 9.750 9.190 9.500 8.880

11.000 10.500 10.750 10.190 10.500 9.880

12.000 11.500 11.750 11.190 11.500 10.880

13.000 12.500 12.750 12.190 12.500 11.880

13.750 13.190 13.500 12.880

14.750 14.190 14.500 13.880

15.750 15.190 15.500 14.880

16.500 15.880

17.500 16.880

FOR LENGTHS SHORTER THAN LISTED, SCREWS WILL BE THREADED AS CLOSE TO THE HEAD AS PRACTICABLE (APPROX. WITHIN 3 THREAD PITCHES).


Shoulder Bolt, Hexagon Recess, Alloy Steel, 95 KSI Ultimate shear strength, Austenitic Stainless Steel, 45 KSI USS and A286, 95 KSI USS

24

TDASH NOM. THREAD SERIES ØA ØB F H ØJ ØK N M +.000 U WNO. SHLDRØ UNRC-3A UNRF-3A MIN. MIN. UNRC UNRF MAX. MAX. -.020 MAX. NOM.

4 .250 .1900-24 .1900-32 .375 .248 .094 .188 .227 .142 .156 .093 .083 .375 .005 .125

.357 .247 .182 .133 .147

5 .312 .2500-20 .2500-28 .438 .3105 .117 .219 .289 .193 .210 .093 .100 .437 .005 .156

.419 .3095 .213 .182 .201

6 .375 .3125-18 .3125-24 .562 .373 .141 .250 .352 .249 .265 .093 .111 .500 .005 .187

.543 .372 .244 .237 .256

8 .500 .3750-16 .3750-24 .750 .498 .188 .313 .477 .304 .327 .093 .125 .625 .008 .250

.729 .497 .306 .291 .318

10 .625 .5000-13 .5000-20 .875 .623 .234 .375 .602 .414 .443 .093 .154 .750 .008 .312

.853 .622 .368 .397 .432

12 .750 .6250-11 .6250-18 1.000 .748 .281 .500 .727 .521 .561 .093 .182 .875 .008 .375

.977 .747 .492 .502 .549

14 .875 .7500-10 .7500-16 1.125 .873 .375 .625 .852 .638 .678 .093 .200 1.000 .008 .500

1.000 .872 .616 .616 .665

16 1.000 .7500-10 .7500-16 1.312 .998 .375 .625 .977 .638 .678 .125 .200 1.000 .008 .500

1.287 .997 .616 .616 .665

20 1.250 .8750-9 .8750-14 1.750 1.248 .469 .750 1.227 .750 .796 .125 .222 1.125 .008 .625

1.723 1.247 .741 .726 .778

24 1.500 1.1250-7 1.1250-12 2.125 1.498 .656 1.000 1.478 .964 1.022 .125 .286 1.500 .008 .875

2.095 1.496 .980 .934 1.014

28 1.750 1.2500-7 1.2500-12 2.375 1.748 .750 1.125 1.728 1.089 1.147 .125 .286 1.750 .008 1.000

2.345 1.746 1.105 1.059 1.139

32 2.000 1.5000-6 1.5000-12 2.750 1.998 .937 1.250 1.978 1.307 1.397 .125 .333 2.000 .008 1.250

2.720 1.996 1.230 1.277 1.389

MARK S OR SPSAS APPLICABLE

STANDARDS AND SPECIFICATIONS: NASM21472

Shoulder Bolt, Hexagon Recess


25

THE TENSILE STRENGTH IS BASED ON A STRESS OF 160 KSI MINIMUM AND THE AREA AT MINIMUM NECK “ØK”. THE SHEAR STRENGTH IS BASED ON A STRESS OF 95 KSIMINIMUM AND THE AREA AT MINIMUM SHOULDER “ØB”.


DOUBLE SHEAR *RECOMMENDEDDASH NOMINAL THREAD SERIES TENSILE STRENGTH STRENGTH OF BODY SEATING TORQUENO. SHLDRØ LBS. MIN. LBS., MIN. INCH POUNDS

UNRC-3A UNRF-3A UNRC-3A UNRF-3A UNRC UNRF

4 .250 .1900-24 .1900-32 2,220 2,720 9,100 45 52

5 .312 .2500-20 .2500-28 4,160 5,080 14,300 112 128

6 .375 .3125-18 .3125-24 7,060 8,240 20,700 230 255

8 .500 .3750-16 .3750-24 10,640 12,710 36,900 388 441

10 .625 .5000-13 .5000-20 19,810 23,450 57,700 990 1,115

12 .750 .6250-11 .6250-18 31,670 37,880 83,300 1,975 2,236

14 .875 .7500-10 .7500-16 47,680 55,570 113,500 3,490 3,900

16 1.000 .7500-10 .7500-16 47,680 55,570 148,300 3,490 3,900

20 1.250 .8750-9 .8750-14 66,230 76,060 232,000 5,610 6,200

24 1.500 1.1250-7 1.1250-12 110,000 129,000 334,000 12,000 12,500

28 1.750 1.2500-7 1.2500-12 141,000 163,000 455,000 16,000 17,500

32 2.000 1.5000-6 1.5000-12 205,000 242,000 595,000 30,000 30,800

MECHANICAL PROPERTIES - ALLOY STEEL

AUSTENITIC STAINLESS STEEL AUSTENITIC STAINLESS STEEL A286 TENSILE A286 DOUBLE SHEARSIZE TENSILE STRENGTH LBS. MIN. DOUBLE SHEAR STRENGTH OF BODY STRENGTH LBS. MIN. STRENGTH OF BODY

UNRC-3A UNRF-3A LBS. MIN. UNRC-3A UNRF-3A LBS. MIN.

4 1,110 1,360 4,300 2,220 2,720 9,100

5 2,080 2,540 6,800 4,160 5,080 14,300

6 3,530 4,120 9,800 7,060 8,240 20,700

8 5,320 6,350 17,500 10,640 12,710 36,900

10 9,900 11,700 27,300 19,810 23,450 57,700

12 15,800 18,900 39,400 31,670 37,880 83,300

14 23,800 27,800 53,700 — — —

16 23,800 27,800 70,300 — — —

20 33,100 38,000 110,000 — — —

24 54,800 64,600 158,000 — — —

28 70,500 81,500 215,000 — — —

32 102,000 121,000 282,000 — — —

AUSTENITIC STAINLESS STEEL — THE TENSILE STRENGTH IS BASED ON A STRESS OF 80 KSI MINIMUM AND THE AREA AT MINIMUM NECK “ØK”. THE SHEAR STRENGTH IS BASEDON A STRESS OF 45 KSI ULTIMATE SHEAR STRENGTH AND THE AREA AT MINIMUM SHOULDER “ØB”.

A286 — THE TENSILE STRENGTH IS BASED ON A STRESS OF 160 KSI MINIMUM AND THE AREA AT MINIMUM NECK “ØK”. THE SHEAR STRENGTH IS BASED ON A STRESS OF 95 KSIMINIMUM AND THE AREA AT MINIMUM SHOULDER “ØB”.

MECHANICAL PROPERTIES-CORROSION RESISTANT




26


94706 - AUSTENITIC STAINLESS STEEL PER CHEMISTRY OF ASTM A493. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1.

95224 - A286 PER CHEMISTRY OF AMS 5853. HRC 36-48. FLUORESCENT PENETRANT INSPECT PER ASTM E1417. ACCEPTANCE CRITERIA PER SPS-I-650.

2. DIMENSIONS AND GEOMETRIC TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1.3. FINISH: REFER TO FINISH OPTIONS.4. PART NUMBERING: ( ) ( ) – ( ) ( ) – ( ) ( )

FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.C-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (ALLOY)NO LETTER-PASSIVATE (CRES)


F-FINE



BASIC PART NUMBER

Set Screw, Hexagon Recess, Various Point Styles, Alloy Steel, Stainless Steel

27

THREAD SIZE A A C D F G H W RUNRC UNRF **

UNRC-3A UNRF-3A MAX. MIN. MAX. MIN. MAX. MIN. MAX. MIN. MAX. MIN. MAX. MIN. MIN. NOM. RAD.#0-80 .0600 .0568 .033 .027 .040 .037 .017 .013 .033 .027 .035 .028 .047

#1-64 #1-72 .0730 .0692 .0730 .0695 .040 .033 .049 .045 .021 .017 .040 .034 .035 .035 .055#2-56 #2-64 .0860 .0819 .0860 .0822 .047 .039 .057 .053 .024 .020 .047 .039 .035 .035 .062#3-48 #3-56 .0990 .0945 .0990 .0949 .054 .045 .066 .062 .027 .023 .054 .046 .060 .050 .078#4-40 #4-48 .1120 .1069 .1120 .1075 .061 .051 .075 .070 .030 .026 .060 .052 .075 .050 .084#5-40 #5-44 .1250 .1199 .1250 .1202 .067 .057 .083 .078 .033 .027 .064 .056 .075 .0625 .093#6-32 #6-40 .1380 .1320 .1380 .1329 .074 .064 .092 .087 .038 .032 .074 .066 .075 .0625 .109#8-32 #8-36 .1640 .1580 .1640 .1585 .087 .076 .109 .103 .043 .037 .084 .076 .075 .0781 .125#10-24 #10-32 .1900 .1828 .1900 .1840 .102 .088 .127 .120 .049 .041 .095 .085 .105 .0937 .1411/4-20 1/4-28 .2500 .2419 .2500 .2435 .132 .118 .156 .149 .0665 .0585 .130 .120 .105 .125 .1885/16-18 5/16-24 .3125 .3038 .3125 .3053 .172 .156 .203 .195 .082 .074 .164 .148 .140 .1562 .2343/8-16 3/8-24 .3750 .3656 .3750 .3678 .212 .194 .250 .241 .0987 .0887 .1955 .1795 .140 .1875 .2817/16-14 7/16-20 .4375 .4272 .4375 .4294 .252 .232 .296 .287 .114 .104 .2267 .2107 .190 .2187 .3281/2-13 1/2-20 .5000 .4891 .5000 .4919 .291 .270 .343 .334 .130 .120 .260 .240 .210 .250 .3759/16-12 9/16-18 .5625 .5511 .5625 .5538 .332 .309 .390 .379 .1456 .1356 .291 .271 .265 .250 .4225/8-11 5/8-18 .6250 .6129 .6250 .6163 .371 .347 .468 .456 .164 .148 .3225 .3025 .265 .3125 .4683/4-10 3/4-16 .7500 .7371 .7500 .7406 .450 .425 .562 .549 .1955 .1795 .385 .365 .330 .375 .5627/8-9 7/8-14 .8750 .8611 .8750 .8647 .530 .502 .656 .642 .2267 .2107 .4475 .4275 .450 .500 .6561-8 1-12 1.0000 .9850 1.0000 .9897 .609 .579 .750 .734 .260 .240 .510 .490 .550 .5625 .750

1-1/8-7 1-1/8-12 1.1250 1.1086 1.1250 1.1136 .689 .655 .843 .826 .291 .271 .5775 .5475 .650 .5625 .8441-1/4-7 1-1/4-12 1.2500 1.2336 1.2500 1.2386 .767 .733 .937 .920 .3225 .3025 .640 .610 .700 .625 .9381-3/8-6 1-3/8-12 1.3750 1.3568 1.3750 1.3636 .848 .808 1.031 1.011 .3537 .3337 .7025 .6725 .700 .625 1.0321-1/2-6 1-1/2-12 1.5000 1.4818 1.5000 1.4886 .926 .886 1.125 1.105 .385 .365 .765 .735 .750 .750 1.125

(a) WHEN LENGTH EQUALS NOMINAL DIAMETER OR LESS, INCLUDED ANGLE IS 118˚. (#4 X 1/8 AND #8 X 3/16 ALSO HAVE 118˚ ANGLE)(b) WHEN LENGTH EQUALS NOMINAL DIAMETER OR LESS, INCLUDED ANGLE IS 130˚.

** VALUES SHOWN IN COLUMN H ARE FOR MINIMUM STOCK LENGTH CUP POINT SCREWS.

UP TO .630 OVER .630 TO 2.0" OVER 2.0" TO 6.0" OVER 6.0"±.01 ±.02 ±.03 ±.06


KNURL CUP(#4 AND LARGER)(SEE NOTE b)


Set Screws, Hexagon Recess, Alloy Steel, AUSTENITIC Stainless Steel

28

BASIC BASICPART POINT PART

NUMBER TYPE NUMBER GENERAL APPLICATIONSALLOY STAINLESSSTEEL STEEL94709 FLAT 94947 USE WHERE PARTS MUST BE FREQUENTLY RE-SET; HARDENED SHAFTS, ADJUSTING SCREW.94710 PLAIN CUP 94948 USE WHERE HIGH TIGHTENING TORQUES ARE IMPRACTICAL; ZINC, DIE CASTINGS.94711 CONE 94950 USE WHERE PERMANENT LOCATION IS NECESSARY; PIVOTS, FINE ADJUSTMENTS.94712 FULL DOG 94974 USE WHERE PERMANENT LOCATION IS NECESSARY; HOLLOW TUBE, REPLACES DOWEL PIN.94713 KNURL CUP 94949 USE FOR QUICK AND PERMANENT LOCATION; GEARS, COLLARS. RESISTS SCREW LOOSENING.94714 OVAL 94951 USE FOR FREQUENT ADJUSTMENT WITHOUT DEFORMATION AND AGAINST ANGULAR SURFACES.94946 HALF DOG 94975 USE WHERE PERMANENT LOCATION IS NECESSARY; HOLLOW TUBE, REPLACES DOWEL PIN.

*REFER TO WARNING ON PAGE 6.DASH *RECOMMENDED SEATING TORQUE IN POUNDSSIZE NUMBER ALLOY STEEL STAINLESS STEEL#0 90 1 .4#1 91 1.8 1.2#2 92 1.8 1.2#3 93 5 4#4 94 5 4#5 95 10 7#6 96 10 7#8 98 20 16#10 3 36 261/4 4 87 705/16 5 165 1303/8 6 290 2307/16 7 430 3401/2 8 620 5009/16 9 620 5005/8 10 1325 9803/4 12 2400 17007/8 14 3600 30001 16 5000 4000

1-1/8 18 7200 56001-1/4 20 9600 77001-3/8 22 9600 77001-1/2 24 11,230 9100

1. MATERIAL: ALLOY STEEL PER AISI 4032, 4037, 40L37SE, 4137, 4140, 8630, 8740 OR EQUIVALENT. 300 SERIES AUSTENITIC STAINLESS STEEL.

2. HEAT TREAT: 45-53 HRC FOR ALLOY STEEL ONLY. FOR ALLOY STEEL PARTS WITH NYLON PLUG - 28 HRC MINIMUM.3. FINISH: SEE NOTE 5.4. DIMENSIONS AND TOLERANCING PER ASME B18.3, THREADS PER ASME B1.1. 5. PART NUMBERING: 94XXX ( ) – ( ) ( ) – ( ) ( )

FINISH = B-CHEMICAL BLACK OXIDE PER MIL-C-13924.C-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 3.D-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 3.H-CADMIUM PLATE PER QQ-P-416, TYPE I, CLASS 2.J-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (YELLOW CHROMATE)M-CADMIUM PLATE PER QQ-P-416, TYPE II, CLASS 2. (OLIVE DRAB)S-SILVER PLATE PER AMS2410.U-ZINC PLATE PER ASTM B633 TYPE III SCI.Z-ZINC PLATE PER ASTM B633 TYPE II SCI.NO LETTER-THERMAL OXIDE (BLACK) PLUS RUST PREVENTATIVE OIL. (ALLOY STEEL)NO LETTER-PASSIVATE PER ASTM A967. (STAINLESS STEEL)


F-FINE= DASH NUMBER (SEE RECOMMENDED SEATING TORQUE TABLE)LOCKING FEATURE = NO LETTER-NO LOCKING FEATURE

E-TYPE P (PATCH) PER MIL-DTL-18240K-TYPE N (PELLET) PER MIL-DTL-18240

BASIC PART NUMBER (SEE GENERAL APPLICATIONS TABLE)

Do the fasteners you arecurrently using meet theFF-S-86 procurementspecification formilitary/governmentsocket screws?

Why do I need SPS certifiedfasteners?Reliability is a crucial issue amongaerospace and defense industrysuppliers and contractors.Fasteners are used in airplanes,aerospace vehicles, satellites,missiles, military vehicles,weapons and other applicationswhere failure cannot be tolerated.MS (Military Standard) and NAS(National Aerospace Standards)fasteners help assure reliability forthese critical uses.

SpecificationsThe FF-S-86 specification coverssocket screws, including shoulderbutton head and flat head styles.Numerous MS and a number ofNAS fastener standards aregoverned by this specification.This specification helps assurereliable part performance.

The Socket Screw ChecklistUnfortunately, sub-standardfasteners represented as MS andNAS parts are being supplied. Thisis why it’s vital that every time youpurchase socket screws for criticalapplications, you should ask thefollowing questions about theproduct and its source:

• Do they manufacture the socketscrews they sell?• Do they certify socket screws toFF-S-86?• Are they experienced workingwith special materials, closetolerances and criticalrequirements?• Do they control theirmanufacturing processes?

• Do they maintain stringentquality assurance for all products?• Do they maintain statisticalmonitoring of all manufacturingphases?• Do they have in-housecapabilities for plating, postplating bake and stress durabilitytesting?• Do they certify plated parts toQQ-P-416?• Do they have in-house magneticparticle and fluorescent penetrantinspection facilities?• Are they approved on the BoeingD590 standards?• Do they offer productengineering assistance withdesign, materials and finishes?

SPS TechnologiesSPS Technologies AerospaceFasteners Group maintains all ofthe capabilities and resources tomeet these exact requirementsand certify fasteners for criticalapplications.

Fatigue FailureAn estimated 85% of fastenerfailures are caused by fatigue.While FF-S-86 includes a numberof quality requirements, it doesnot specify fatigue failuresafeguards. SPS Technologiesmanufactures socket screwproducts that exhibit high fatigueresistance to assure maximumjoint reliability and safety. Toachieve the highest degree ofsafety and reliability, you shouldconsider including fatiguerequirements in yourspecifications.

Why parts do not meetstandardsAssuring compliance with theprocurement specification iseveryone’s concern. However,ignorance, confusion, laxity, evendisregard have all played a part inthe rise in the number of partswhich do not meet standards.

Price sensitivity, deliverypressures and governmentsourcing constraints are alsofactors. The results are partfailures, lower safety standards,downtime, repair expenses andextra manhour costs.

What else can I do?As discussed in the Socket ScrewChecklist, you should requireparts certification from yoursource. Setting up incomingquality control inspections canalso help.

The most important step isacquiring a full understanding ofthe FF-S-86 requirements and theproblems that can result whensub-standard parts are introducedinto full production schemes.

Do your socket screws measure up?

29

FF-S-86 is the procurementspecification for both MS and NASsocket head cap screws. FederalSpecification QQ-P-416 (cadmiumplating) and ASME B18.3 (socketcap, shoulder and set screws) alsoform a part of this specification.

Within these documents otherspecifications are referenced.General topics under thespecification include material,mechanical properties, dimensions,tolerances, thread laps, plating,carburization/decarburizationlimitations, discontinuity limitations,hydrogen embrittlement, qualityassurance and testing.

One significant problem with partswhich are represented as MS orNAS fasteners, but are not, is thatsuppliers fail to recognize or adhereto the secondary specifications,such as QQ-P-416 (when plating isrequired), or even the basic

dimensional requirements of theAmerican National StandardsInstitute (ASME B18.3).

Manufacturing RequirementsStringent control of allmanufacturing processes is criticalto the production of fasteners thatmeet specifications. Doubtless,certain manufacturing practicesproduce better products thanothers. Properly forged heads androlled threads produce thestrongest, most reliable fasteners.

Forging forms the metal andactually makes the heads stronger.Machined heads and cut or groundthreads are less satisfactory.Machining—actually cutting themetal—weakens fasteners, invitingfatigue failure.

More ConsiderationsDesign is another importantelement in meeting specifications.Heads must be designed withproper bearing area, correct upsetand controlled fillet radius. Socketdepth must conform to dimensionalrequirements in order to developproper tightening characteristics.

Proper selection of material, properheat treating, control of criticalplating procedures and well-equipped quality control and testingfacilities are all important, too.

Failures ResultFailure to correctly control any ofthese and other manufacturingprocesses can allow fastenerswhich do not meet specification tofind their way into the MS and NASsystems. These substandardfasteners can lead to prematurefailures and attendant problems inthe field.

30

Understanding FF-S-86

What to Look for...WhatCan HappenGenerally, specification-relatedproblems can be classed in one offour areas: dimensions,mechanical/physical, plating andquality assurance. The following isa discussion of the variousproblems.

DimensionalProblem Areas - What to Look For• Insufficient socket depth causesinadequate key engagement• Excessive socket depth reducesthe amount of material in thehead, lowering screw strength• Undersize threads can lead tostripping • Undersize fillet may promotestress failure• Poorly formed thread runout maycause fatigue failure

All MS and NAS socket screwproducts must conform to thedimensional requirements ofASME B18.3. This is the overallinch standard for socket screwproducts and keys related to thefollowing requirements...

Dimensional Basics• Body and head diameter• Head height• Head side height• Socket width• Fillet radius• Wall thickness• Key engagement• Chamfer• Basic thread length

Problem Scenarios - WhatCan Happen1. Excessive socket depth causedpremature fatigue in this part(pictured at right). Full screwstrength was not achievedbecause the socket depthexceeded the maximum allowedand the wall thickness betweenthe bottom of the socket and thehead bearing surface wasinadequate. When socket depth isunder minimum requirements,limited key engagement canprevent maximum tightening andreduce load carrying capacity.Limited key engagement in thiscase can also lead to screw failureat low wrenching torques.

Undersize threads can causethread stripping. Insufficientmaterial in the screw blank orimproper adjustment of the threaddies are two possible causes.(Ref. MS 24678)

2. This fastener failed prematurelybecause of a high stressconcentration in the fillet area(pictured at right). An undersizefillet and machining marks werethe cause. Fillet must be smoothand within the minimum/maximumdimensions of ASME B18.3. (Ref.MS 24678)

3. A poorly formed thread runout(last thread) caused this fastenerto fail in fatigue (pictured at right).When a thread runout is notproperly radiused, a high stressconcentration is created andpremature fatigue failures canoccur.

31

Fasteners that don’t meet MS & NAS Specifications

1.

2.

3.

Mechanical PropertiesProblem Areas - What to Look For• Improper material selectionlowers part quality, causesinconsistent hardness • Poor control of heat treatinglowers tensile strength values• Carburization which can reducefatigue life and promote hydrogenembrittlement• Decarburization which candegrade fastener strength andperformance

The procurement specificationrequires that fasteners exhibitspecific strength and hardnessproperties. Material choice, heattreatment practices, hardenabilityand carburization/decarburizationlimitations all play a part inachieving these mechanicalproperties.

Problem Scenarios - WhatCan Happen1. Start with the right material -Specifications call for heat-treatablealloy steel, corrosion resistant steelor specific non-ferrous materials.Any material deviation could resultin parts failure.

2. Heat treatment - Parts are heattreated to develop the desiredstrength and hardness levels. Poorheat treatment practices can resultin an inferior product. Proper heattreatment requires...

• Controlled furnace atmospheresto prevent carburization anddecarburization• Close temperature control toprevent detrimental microstructuralchanges• Proper quenching medium toprevent cracking and ensurethrough-hardening

The ability of a part to be through-hardened upon quenching alsodepends on the hardenability of thealloy selected, which is a function

of chemical composition. Improperalloy selection can result inundesirable hardness variationswithin the part.

Carburization is an increase insurface carbon content, whichmakes the surface harder than thecore. Carburized fasteners tend toexhibit reduced fatigueperformance, are less able towithstand bending stresses and aremore susceptible toenvironmentally-assisted failure(i.e., stress corrosion cracking andhydrogen embrittlement).If a part is being plated,

carburization can increasesusceptibility of the part tohydrogen embrittlement.

Decarburization is a decrease insurface carbon content, whichmakes the surface softer than thecore. Decarburized fasteners tendto exhibit reduced fatigueperformance.

Carburization and totaldecarburization must not bepresent on the thread surfaceaccording to the requirements ofFF-S-86.

32

Start measurements at point “C” and continue toward crest along line A-A.

PARTIALDECARBURIZATION

A

.1 Hb

2/3 Hb

A

C

Figure 1Definition of Partial Decarburization Limits(federal Specification, FF-S-86, screw, cap, socket head)

PlatingProblem Areas - What to Look For• Cold work without stress relief,heavy chemical cleaning andimproper control of plating orbaking processes can causehydrogen embrittlement anddelayed fracture failures• Plating of off-the-shelf parts canresult in unacceptable platingthickness• “Flash” plating of off-the-shelffasteners can reduce corrosionresistance

Poor plating practice is one of themajor reasons fasteners fail tosatisfy MS and NAS specificationrequirements. To avoid problems,good plating practices must befollowed: proper cleaning, stressrelief, plating thickness control,post plating bake to specificationand rigorous quality control.

Failure to carefully monitor any ofthese criteria can result inhydrogen embrittlement problems,out-of-tolerance threaddimensions, uneven platingthickness or inadequate corrosionresistance.

Problem Scenarios - WhatCan Happen1. Hydrogen Embrittlement -Classic hydrogen embrittlementoccurs in three steps:

• Hydrogen present in metal underload diffuses to the points ofhighest stress• Hydrogen then migrates tointerfaces (i.e., boundaries)• Discrete crack growth occursuntil the cross-sectional area ofthe metal is sufficiently reducedfor over-stress failure to ensue

Hydrogen embrittlement is aserious concern with fastenerssupplied to MS/NAS specificationbecause their higher tensilestrengths make them moresusceptible. Preventativemeasures rely on the use ofplating and post plating bakepractices that minimize thepotential for hydrogen pick-up.

Cold WorkCold work—machining, grinding,cold forming and coldstraightening—which follows heattreating can cause residualsurface tensile stresses and thuspromote hydrogen embrittlement.cold worked parts must undergo astress relief operation beforeplating. Stress relief is requiredunder QQ-P-416.

CleaningHeavy acid cleaning to removeheat treat scale and foreign mattercan add large amounts ofhydrogen to parts and encouragehydrogen embrittlement. Cleaningmethods must be controlledaccording to type and material offastener. Aggressive acid solutionsshould be avoided.

Post PlatingBakingThe FF-S-86 specification requiresalloy steel cap screws be baked tominimize the embrittlementpotential that results from theplating process. Specifications callfor a 23 hour bake at 375 ±25°Fwithin four hours of plating.

CertificationMS and NAS coated alloy steelscrews must be furnished withcertification of hydrogenembrittlement relief treatment and,when specified, must be subjectedto a stress durability test.Manufacturers and sub-contractedplaters often are not equipped toperform this and other importanttesting.

2. Plating Thickness - Platingthickness seems simple enough.However, because of the threadconfiguration, a screw’s pitchdiameter is increased by fourtimes the plating thickness (seediagram, Fig. 2). To maintain thepitch diameter within specifiedlimits, part tolerances must becontrolled to allow for the extrathickness added by plating.

33

PITCHLINEAFTERPLATING

PITCHLINE

BEFOREPLATING

HAS INCREASED .0012

PITCHLINE

AFTERPLATING

PITCHLINEBEFOREPLATING

PITCH DIAMETERAFTER PLATING

PITCH DIAMETERBEFORE PLATING

C

C

C

C

B

B

B

B

.0006"

.0006"

.000

3"

.0003" .000

3"

.0003"

30° 60°

90°

30° 60°

90°

.0006"

.0006"

30°60°

90°

30°60°

90°

Sketch is out of scale to illustrate Four-Thickness Principle

Figure 2

If off-the-shelf fasteners aresupplied for plating, statisticalanalysis shows that, on-average,16% of the plated screws will beoversize. Only by making thefasteners properly undersize will100% of the finished plated partsfall within tolerance.

Often, off-the-shelf fasteners are“flash” plated to avoid the pitchdiameter thickness problem. Thisshort-cut can result in reducedcorrosion resistance.

Carelessness in the platingprocedure can also lead to unevenplating thickness and inadequateprotection against corrosion. Poorcontrol of the plating current cancause a too-rapid deposit of platingand an uneven build-up on thethreads. The plating thickness willtend to be greater on the crests,meeting gage limits, but the depositon the flanks and roots of threadsmay be too thin to provide thenecessary protection.

Quality AssuranceProblem Areas - What to Look For• Flawed parts reach users becauseof lax quality control• Breakdowns in process controlcan result in defective fasteners

Comprehensive quality assuranceprocedures are obviousprerequisites in the manufacture ofMS and NAS fasteners. Specificand thorough testing is requiredunder the procurementspecification. It would be virtuallyimpossible to maintain the highstandard required with theseproducts without such control.

Under the specificationrequirements, lot sampling must beperformed for defects, mechanicaland metallographic properties andprotective coatings.

Specific test procedures and qualitystandards must be adhered to forMS and NAS fasteners. Testingmust be performed by themanufacturer or an independentfacility.

Even the simplest inspections oftenare not performed. Many parts withdiscontinuities unacceptable underthe standards are put into use. Aclose final inspection would havescreened out sub-standard parts.

Problem Scenarios - What Can Happen1. Parts from this lot failed infatigue (pictured at right). Threadlaps below the pitch diameter may be caused by broken, chipped or misaligned dies. Thediscontinuities are in an area of thescrew thread that is the mostcritical and most highly stressedarea of the fastener in dynamicapplications.

2. These forging cracks werecaused by poor manufacturingpractices (pictured at right). Theirlocation is in an area of the headthat is unacceptable under therequirements of FF-S-86 and maycause the socket to split under thestress of installation.

Process control is anotherimportant aspect of qualityassurance. Without carefulmonitoring at every step of themanufacturing process, problemssuch as this can arise. (Ref. MS24678)

3. This socket reamed at well belowthe recommended seating torque(pictured at right). To facilitate crossdrilling the lockwire hole, the screwwas annealed after the heattreatment procedure. However, thepart was never re-heat treated.Cross drilling must always beperformed either before heattreatment or in the heat treatedcondition.

SpecificationsFF-S-86Federal Specification, screw, cap,socket head (Superintendent OfDocuments, U.S. GovernmentPrinting Office, Washington, DC20402)

ASME B18.3Socket cap, shoulder and setscrews (American NationalStandards Institute, 1430 Broadway,New York, NY 10018)

QQ-P-416Federal Specification, plating,cadmium (electrodeposited)(Superintendent Of Documents,U.S. Government Printing Office,Washington, DC 20402)

343.

2.

1.

35

Products listed as MilitaryStandards have beenmanufactured to meet or exceedthose standards. To verify latestqualifications status, contactSPS Technologies AerospaceProducts Customer ServiceDepartment.

Reworking, modifying, plating orre-plating, altering or causingthe same to be done on any SPSproduct as manufactured,certified and supplied by SPSTechnologies is prohibited. Inthe event that such action istaken, product cannot berepresented as SPS product.

The standards contained hereintake precedence overdocuments reference herein.Referenced drawings, standardsand documents shall be of theissue in effect on date ofinvitation to bid. Sales/catalogdrawings and part numbers arefor ordering purposes only.

THE REMEDY PROVIDED FORHEREIN SHALL BE THEEXCLUSIVE REMEDY FOR ANYBREACH OF WARRANTY ORANY CLAIM ARISING IN ANYWAY OUT OF THEMANUFACTURE, SALE, OR USEOF THESE PRODUCTS. In noevent shall SPS Technologies beliable for consequential,incidental or any other damagesof any nature whatsoever exceptthose specifically providedherein for any breach ofwarranty or any claim arising inany way of the manufacture,sale, or use of these products.No other person is authorized bySPS Technologies to give anyother warranty, written or oral,pertaining to the products.

Drawings subject to revision. Toassure you have currentdrawings contact SPSTechnologies Aerospace ProductEngineering Dept.

SPS Technologies through itsAerospace Products warrantsthat these products conform toindustry standards specifiedherein and will be free fromdefects in materials andworkmanship. THIS WARRANTYIS EXPRESSLY GIVEN IN LIEUOF ANY AND ALL OTHEREXPRESS OR IMPLIEDWARRANTIES, INCLUDINGANY IMPLIED WARRANTY OFMERCHANTABILITY ORFITNESS FOR A PARTICULARPURPOSE, AND IN LIEU OFANY OTHER OBLIGATION ONTHE PART OF SPSTECHNOLOGIES. SPSTechnologies will at its option,repair or replace free of charge(excluding all shipping andhandling costs) any productswhich have not been subject tomisuse, abuse, or modificationand which in its soledetermination were notmanufactured in compliancewith the warranty given above.

Limited Warranty and Exclusive Remedy

301 Highland Ave., Jenkintown, PA 19046 • 215-572-3000 • fax 215-572-3133 • www.spstech.com/aero

SPS and TRU-FLEX are registered trademarks of SPS Technologies. NYTEMP is a registered trademark of NYLOK Fastener Corporation.

© 2005 SPS Technologies All rights reserved 5525Rev3 TSI 03/05 1M Printed in USA